A Research Guide for
Herpes (HSV-1, HSV-2 & Shingles)

• Traditional association: Oral herpes (cold sores, fever blisters)
• Changing epidemiology: HSV-1 now accounts for an increasing proportion of genital herpes cases, particularly in younger adults and in developed countries. In some populations, HSV-1 causes 30–50% of new genital herpes diagnoses.
• Latency site: Trigeminal ganglia (oral) or sacral ganglia (genital)
• Recurrence pattern: Oral HSV-1 recurs in roughly 20–40% of infected individuals, averaging 1–2 outbreaks per year. Genital HSV-1 recurs less frequently than genital HSV-2 — typically averaging less than one recurrence per year after the first year, and many patients have no recurrences.
• Asymptomatic shedding: Present but less frequent than HSV-2
• Complications: Herpes labialis (cold sores), herpetic whitlow (finger infection), herpes keratitis (eye involvement — a leading infectious cause of corneal blindness), and rarely herpes encephalitis

• Primary association: Genital herpes
• Transmission: Almost exclusively through sexual contact (genital-genital, oral-genital, or genital-anal)
• Latency site: Sacral ganglia
• Recurrence pattern: More frequent than HSV-1 genital infection. First-year average is 4–6 recurrences, declining over subsequent years. Individual variation is wide — some people have monthly outbreaks, others have one every few years.
• Asymptomatic shedding: Occurs on roughly 10–20% of days in the first year, declining over time. This is the primary mode of transmission to partners — most HSV-2 transmission occurs from partners who are not aware they are shedding virus.
• Relationship to HIV: HSV-2 increases susceptibility to HIV acquisition by 2–3 fold, and HIV increases HSV-2 shedding and severity.
• Complications: Recurrent genital ulcers, neonatal herpes (rare but serious), aseptic meningitis (Mollaret meningitis), sacral radiculopathy, and urinary retention during primary episodes

• Primary infection: Varicella (chickenpox), typically in childhood
• Reactivation disease: Herpes zoster (shingles) — a painful, blistering rash in a dermatomal distribution (one side of the body, following a single nerve path)
• Latency site: Dorsal root ganglia and cranial nerve ganglia along the entire spinal column
• Lifetime risk: Approximately 30% of people who have had chickenpox will develop shingles. Risk increases significantly after age 50 and in immunocompromised individuals.
• Complications:
  • Postherpetic neuralgia (PHN): The most feared complication — persistent nerve pain lasting months to years after the rash resolves. Affects 10–18% of shingles patients overall, rising to 30% or more in those over 60.
  • Herpes zoster ophthalmicus (HZO): Shingles involving the eye (V1 trigeminal distribution) — can cause keratitis, uveitis, and vision loss. Requires urgent ophthalmologic evaluation.
  • Ramsay Hunt syndrome: VZV reactivation in the facial nerve — causes facial paralysis, ear pain, and vesicles in the ear canal.
  • Disseminated zoster: Widespread shingles in immunocompromised patients — can affect multiple dermatomes and internal organs.
• Vaccine: Shingrix (recombinant, adjuvanted) is over 90% effective at preventing shingles and PHN.

• HSV-1 oral: Direct skin-to-skin contact with an infected area — kissing, sharing utensils, sharing lip products. Most commonly acquired in childhood from family members. Transmission can occur even without visible cold sores.
• HSV-1 genital: Oral-genital contact (receiving oral sex from someone with oral HSV-1). This has become the most common cause of first-episode genital herpes in many populations.
• HSV-2: Genital-genital, genital-anal, or rarely oral-genital contact. The virus sheds asymptomatically from genital skin and mucous membranes.
• VZV: Airborne transmission (respiratory droplets) for chickenpox; direct contact with shingles lesions for zoster. A person with shingles can transmit chickenpox (not shingles) to someone who has never had chickenpox or the vaccine.

What does NOT transmit herpes: Toilet seats, swimming pools, hot tubs, shared towels or bedding (unless there is direct contact with wet lesion fluid), casual social contact, hugging, or handshaking.

No method eliminates transmission risk entirely, but the combination of multiple strategies reduces it substantially:

• Daily suppressive antiviral therapy: Reduces HSV-2 transmission to uninfected partners by approximately 48% (landmark Corey et al. NEJM 2004 trial). Also reduces viral shedding by 80–90%.
• Consistent condom use: Reduces transmission by approximately 30–50% for male-to-female and female-to-male transmission.
• Combination (antivirals + condoms): Together these reduce per-year transmission risk to low single-digit percentages.
• Avoiding sexual contact during outbreaks: Reduces risk, though asymptomatic shedding means transmission can occur at any time.
• Disclosure to partners: Allows informed decision-making and planning. See the Disclosure section below.

Transmission risk figures to put in perspective: without any precautions, the annual risk of HSV-2 transmission from an infected male to an uninfected female partner is approximately 10%. From an infected female to an uninfected male, roughly 4%. With suppressive therapy and condoms, these numbers drop to approximately 2% and 1% respectively.

Asymptomatic viral shedding — the presence of virus on skin or mucous membranes without visible lesions — is the most common way herpes is transmitted to new partners. Studies using daily genital swab PCR have shown:

• HSV-2 shedding occurs on approximately 10–20% of days in the first year after infection, declining to roughly 5–10% over subsequent years.
• HSV-1 genital shedding is less frequent — roughly 3–5% of days.
• Shedding episodes are typically brief (lasting hours to a day or two) and intermittent.
• Suppressive antiviral therapy reduces shedding frequency by 80–90% but does not eliminate it entirely.

This is why complete prevention of transmission is not currently possible, and why honest disclosure and shared decision-making with partners are more realistic and humane approaches than attempting to guarantee zero risk.

• Claims of a “cure” for herpes: No treatment currently cures herpes. Any product claiming to do so is misleading. Research toward a cure is active and promising, but no cure is available today.
• Testimonial-based evidence: Anecdotes are not evidence. Herpes naturally has periods of remission, so any treatment started before a natural remission may appear to “work.”
• Claims that doctors are “hiding” the cure: Conspiracy-theory marketing. The researchers working on herpes cures would be among the first to announce success.
• Expensive supplements or protocols: If a treatment were genuinely effective, it would be studied, validated, and prescribed. Products sold only through direct marketing or proprietary websites should be viewed with extreme skepticism.
• Lysine megadoses: Lysine supplementation has been studied and results are inconsistent at best. Small trials show marginal or no benefit. It is not harmful in normal doses but should not be considered a substitute for antiviral medication.

When a suspicious lesion is present, direct testing of the lesion is the most reliable approach:

• PCR (polymerase chain reaction) swab: The gold standard. Detects viral DNA in the lesion with very high sensitivity and specificity. Also determines whether the virus is HSV-1 or HSV-2 — this distinction matters for prognosis and counseling. PCR is 4 times more sensitive than viral culture.
• Viral culture: A swab is placed in transport medium and the virus is grown in the laboratory. Less sensitive than PCR (sensitivity drops rapidly as lesions begin to heal), but still specific. Being replaced by PCR at most institutions.
• Direct fluorescent antibody (DFA) testing: Rapid but less widely available. Can distinguish HSV-1 from HSV-2.
• Tzanck smear: A scraping of the lesion base examined under a microscope for multinucleated giant cells. Quick and inexpensive but cannot distinguish HSV-1 from HSV-2 or HSV from VZV. Sensitivity is only 40–60%. Largely superseded by PCR.

Timing matters: Swab testing is most reliable when lesions are fresh (vesicular or early ulcerative stage). Sensitivity drops significantly as lesions begin to crust and heal. If possible, have lesions swabbed within the first 48–72 hours.

When no active lesion is present, blood tests (serology) can detect antibodies to HSV, indicating past infection:

• Type-specific IgG antibody tests: The recommended serologic test. Detects antibodies to glycoprotein G (gG), which differs between HSV-1 (gG-1) and HSV-2 (gG-2). Examples include HerpeSelect and Biokit. Takes 2–12 weeks after infection for antibodies to become detectable (the “window period”).
• Western blot (University of Washington): The gold standard confirmatory test for HSV-2 serology when initial results are equivocal or when greater accuracy is needed. Sensitivity 99%, specificity 99%. Performed at the University of Washington Clinical Virology Laboratory.
• IgM testing: NOT recommended. IgM tests for HSV are unreliable, cannot distinguish between HSV-1 and HSV-2, may be positive during reactivation (not just primary infection), and have high rates of false positives. If your provider orders an HSV IgM test, discuss whether a type-specific IgG or PCR swab would be more appropriate.

Important limitation of serology: A positive HSV-2 IgG result with an index value between 1.1 and 3.5 has a significant false-positive rate (up to 50% in low-prevalence populations). The CDC recommends confirmatory testing with a second assay (such as the Biokit or Western blot) for index values in this range.

Shingles is usually diagnosed clinically based on the characteristic presentation: a painful, blistering rash in a dermatomal distribution (one side of the body, following a single nerve root). However, laboratory confirmation is important in atypical cases:

• PCR of lesion fluid: Gold standard. Confirms VZV and distinguishes from HSV.
• DFA of lesion scraping: Rapid confirmation, VZV-specific.
• Serology: Rising VZV IgG titers can support the diagnosis but are not typically needed.

Shingles can occasionally present without a visible rash (zoster sine herpete) — dermatomal pain without blisters. This is difficult to diagnose and may require specialized testing or a trial of antiviral therapy.

Routine screening for HSV in the general population is not recommended by the CDC or USPSTF due to the limitations of serologic testing and the psychological impact of a positive result in asymptomatic individuals. However, testing is appropriate in specific situations:

• Anyone with genital lesions suspicious for herpes (PCR swab)
• Sexual partners of people with known genital herpes
• People with HIV (HSV-2 testing is recommended as part of comprehensive STI screening)
• People presenting for STI evaluation who specifically request herpes testing
• Pregnant women with partners known to have genital herpes (to determine susceptibility)
• People with recurrent genital symptoms of uncertain cause

1. Confirm the diagnosis is correct. Know which virus you have (HSV-1, HSV-2, or VZV) and what test was used. If the diagnosis is based on serology with a low positive index value (1.1–3.5 for HSV-2), ask about confirmatory testing.
2. Start treatment if symptomatic. If you are having a primary outbreak, antiviral medication (valacyclovir, acyclovir, or famciclovir) started promptly shortens the episode and reduces severity.
3. Ask about suppressive therapy. Discuss with your provider whether daily suppressive therapy is appropriate based on outbreak frequency, desire to reduce transmission, and personal preference.
4. Learn the facts. Many patients discover that what they “knew” about herpes was inaccurate. Reliable sources include the CDC, ASHA (American Sexual Health Association), and the WHO.
5. Give yourself time. The emotional adjustment takes longer than the physical healing. This is normal. Consider speaking with a counselor if feelings of shame, anxiety, or depression persist.

• Which herpes virus do I have — HSV-1 or HSV-2? What test confirmed this?
• Is this likely a primary (first) infection or a reactivation?
• Should I be on antiviral treatment now? Should I consider daily suppressive therapy?
• What is the expected pattern of recurrences for my type and location?
• What are the risks and precautions for sexual partners?
• Do I need additional STI screening?
• If I am pregnant or planning pregnancy, what should I know?

1. Confirm the diagnosis with the right test. Know your virus type (HSV-1 vs HSV-2), the test used, and whether confirmatory testing is needed.
2. Get antiviral treatment for active symptoms. Start promptly for primary outbreaks and within 72 hours for shingles.
3. Discuss suppressive therapy. Appropriate for frequent recurrences (≥6 per year), serodiscordant partnerships, or significant psychological burden from outbreaks.
4. Understand transmission and prevention. Learn about asymptomatic shedding, condom use, and the combination approach to reducing partner risk.
5. Address the emotional impact. Seek support from reliable sources, consider counseling, and recognize that adjustment takes time.
6. If over 50 or immunocompromised: get Shingrix. Two-dose vaccination schedule. Over 90% effective at preventing shingles.

All three drugs are equally effective when used at appropriate doses. Choice is usually based on convenience, cost, and patient preference. Valacyclovir is the most commonly prescribed due to its convenient dosing schedule.

A first episode of genital herpes is typically the most severe and warrants treatment in all cases. CDC-recommended regimens (2021 guidelines, updated 2024):

• Acyclovir 400 mg orally three times daily for 7–10 days
• Valacyclovir 1 g orally twice daily for 7–10 days
• Famciclovir 250 mg orally three times daily for 7–10 days

Treatment should be started as soon as possible. It can be extended beyond 10 days if lesions are not fully healed. Severe primary episodes (extensive lesions, urinary retention, systemic symptoms) may require IV acyclovir and hospitalization.

For patients who prefer to treat outbreaks as they occur rather than taking daily medication. Effectiveness depends on starting treatment within 24 hours of symptom onset (ideally during the prodrome — tingling, itching, or burning before lesions appear).

• Acyclovir 400 mg orally three times daily for 5 days, or 800 mg twice daily for 5 days, or 800 mg three times daily for 2 days
• Valacyclovir 500 mg orally twice daily for 3 days, or 1 g once daily for 5 days
• Famciclovir 125 mg orally twice daily for 5 days, or 1 g twice daily for 1 day, or 500 mg once, followed by 250 mg twice daily for 2 days

Episodic treatment typically shortens outbreaks by 1–2 days. Many patients keep a prescription on hand to start immediately at the first sign of prodromal symptoms.

Oral antivirals for herpes are among the safest medications in medicine:

• Common side effects: Headache, nausea (generally mild and transient)
• Uncommon: Dizziness, abdominal pain
• Rare: Renal impairment (primarily with high IV doses or in patients with pre-existing kidney disease — maintain adequate hydration). Thrombotic thrombocytopenic purpura (TTP/HUS) has been reported rarely with very high doses of valacyclovir in severely immunocompromised patients (HIV with CD4 <100).
• Pregnancy: Acyclovir has the most extensive pregnancy safety data, with registries showing no increase in birth defects. Valacyclovir is considered safe in pregnancy based on its conversion to acyclovir. Both are used routinely from 36 weeks to reduce recurrence at delivery.
• Long-term safety: Patients have taken suppressive acyclovir or valacyclovir continuously for 10–20 years with no significant cumulative toxicity in published data.

CDC-recommended suppressive regimens:

• Acyclovir 400 mg orally twice daily
• Valacyclovir 500 mg orally once daily (for patients with ≤9 recurrences/year) or 1 g once daily
• Famciclovir 250 mg orally twice daily

Benefits:

• Reduces recurrence frequency by 70–80%
• Reduces asymptomatic viral shedding by 80–90%
• Reduces HSV-2 transmission to susceptible partners by approximately 48% (Corey et al., NEJM 2004)
• Significant psychological benefit — reduced anxiety about outbreaks and transmission
• Can improve quality of life and sexual confidence

Considerations:

• Requires daily medication adherence
• Cost (though generics are typically affordable — valacyclovir 500 mg generic often costs under $20/month)
• Reassess periodically (annually) whether suppressive therapy is still needed — outbreak frequency often decreases over years

• Six or more recurrences per year (traditional threshold, though many providers offer it for fewer)
• Serodiscordant couples (one partner has herpes, the other does not) who want to reduce transmission risk
• Significant psychological distress from outbreaks or fear of outbreaks
• Immunocompromised patients (HIV, transplant recipients, chemotherapy)
• Patients who want to reduce the risk of asymptomatic shedding
• Patient preference — some patients simply prefer the peace of mind of daily therapy regardless of outbreak frequency

• Infrequent recurrences (1–2 per year or fewer)
• Mild recurrences that resolve quickly
• No current sexual partner or partner already has the same virus type
• Patient preference for taking medication only when needed
• Genital HSV-1 (which typically recurs much less frequently than HSV-2)

Antiviral therapy should be started within 72 hours of rash onset whenever possible. Treatment is recommended for all patients over 50, immunocompromised patients, patients with moderate-to-severe pain or rash, and patients with ophthalmic (eye) or otic (ear) involvement, regardless of timing.

• Valacyclovir 1 g orally three times daily for 7 days (preferred for convenience)
• Famciclovir 500 mg orally three times daily for 7 days
• Acyclovir 800 mg orally five times daily for 7–10 days (less convenient dosing schedule)

Severe or disseminated shingles, especially in immunocompromised patients, may require IV acyclovir (10 mg/kg every 8 hours).

PHN is defined as pain persisting more than 90 days after rash onset. It is the most common and most debilitating complication of shingles, affecting roughly 10–18% of all shingles patients and up to 30% of those over 60. The pain can be burning, stabbing, or aching, and can be severe enough to interfere with sleep, daily activities, and quality of life.

Treatment options for PHN:

• First-line: Gabapentin (900–3,600 mg/day in divided doses; titrate slowly), pregabalin (150–600 mg/day), or tricyclic antidepressants (nortriptyline or amitriptyline, starting 25 mg at bedtime, titrating to 75–150 mg)
• Topical: Lidocaine 5% patches (up to 3 patches for 12 hours daily), capsaicin 8% patch (single application in clinic, may provide 3 months of relief)
• Second-line: Duloxetine, tramadol, or other opioids for severe cases unresponsive to first-line treatments (with appropriate caution regarding opioid risks)
• Interventional: Nerve blocks, spinal cord stimulation, or intrathecal drug delivery for refractory cases

Prevention of PHN: The most effective prevention is vaccination with Shingrix before shingles occurs. Prompt antiviral treatment within 72 hours of rash onset may reduce but does not eliminate the risk of PHN.

Shingles involving the ophthalmic division (V1) of the trigeminal nerve is a medical urgency. Approximately 10–20% of shingles cases involve this dermatome. Without treatment, up to 50% of patients with HZO develop ocular complications including keratitis, uveitis, and secondary glaucoma.

• Hutchinson sign: Vesicles on the tip or side of the nose indicate involvement of the nasociliary nerve and strongly predict ocular complications. Any patient with this finding should be urgently evaluated by ophthalmology.
• Treatment: Systemic antivirals (valacyclovir, famciclovir, or IV acyclovir) plus urgent ophthalmologic evaluation and management. Topical antivirals, corticosteroids, or cycloplegics may be added based on ophthalmologic findings.
• Follow-up: Prolonged ophthalmologic follow-up is needed even after the acute episode resolves, as delayed complications can occur weeks to months later.

• Efficacy against shingles: Over 97% in adults aged 50–69 and roughly 91% in adults 70 and older (ZOE-50 and ZOE-70 phase 3 trials)
• Efficacy against PHN: Over 90% across all age groups studied
• Durability: Protection remains above 85% through at least 10 years based on published follow-up data
• Who should receive it:
  • All adults aged 50 and older (ACIP recommendation, regardless of prior chickenpox history or prior Zostavax vaccination)
  • Adults aged 19 and older who are immunocompromised (HIV, organ transplant, stem cell transplant, active malignancy, autoimmune disease on immunosuppressive therapy, high-dose corticosteroids) — ACIP expanded recommendation, 2021
• Schedule: Two intramuscular doses, 2–6 months apart. Both doses are needed for full protection.
• If previously vaccinated with Zostavax: Shingrix is recommended even if Zostavax was previously received. Zostavax (live attenuated) was less effective and its protection waned significantly after 5 years.

Shingrix is a potent vaccine that produces strong side effects in many recipients — this reflects its strong immune stimulation and does not indicate a safety problem:

• Very common (expected): Injection site pain (78%), redness, swelling. Muscle pain, fatigue, headache, shivering, fever, and GI symptoms (reported by 45–55% of recipients)
• Duration: Side effects typically last 1–3 days. They are more common after the second dose.
• Serious adverse events: Rare. Guillain-Barré syndrome has been reported at very low rates and is under ongoing surveillance.
• Contraindications: Severe allergic reaction to a vaccine component. Shingrix should be delayed during an active shingles episode (vaccinate after the acute episode resolves).

Cost and insurance: Shingrix is covered by most private insurance plans, Medicare Part D (since the Inflation Reduction Act eliminated cost-sharing for ACIP-recommended vaccines under Part D), and many state immunization programs. Without insurance, the retail cost is approximately $150–200 per dose. The GSK patient assistance program may help uninsured patients.

Patients with HIV, organ transplant recipients, those on chemotherapy or immunosuppressive therapy, and those with primary immunodeficiencies face higher risks from herpes viruses:

• More frequent and more severe HSV recurrences
• Higher risk of disseminated disease (widespread skin or visceral involvement)
• Higher risk of acyclovir-resistant HSV (seen in roughly 5–7% of HSV isolates from immunocompromised patients)
• Higher risk of shingles, disseminated zoster, and PHN

Management considerations:

• Higher doses and longer courses of antivirals may be needed
• Suppressive therapy is generally recommended for all immunocompromised patients with recurrent herpes
• Acyclovir-resistant HSV may require IV foscarnet or topical cidofovir — managed by infectious disease specialists
• Shingrix vaccination is recommended for immunocompromised adults 19 and older (ACIP 2021). Timing relative to immunosuppressive therapy should be discussed with the medical team.

The relationship between HSV-2 and HIV is clinically important:

• HSV-2 increases the risk of HIV acquisition by 2–3 fold (genital ulcers break the mucosal barrier and recruit HIV target cells)
• HIV increases HSV-2 shedding frequency and severity
• HSV-2 reactivation may increase HIV viral load
• All people with HIV should be tested for HSV-2
• Suppressive HSV therapy does not prevent HIV acquisition in HSV-2-positive individuals (studied in large trials), but it reduces HSV-related symptoms and genital ulceration

HSV keratitis is the leading infectious cause of corneal blindness in developed countries. It most commonly involves HSV-1 and can affect any layer of the cornea:

• Epithelial keratitis: The classic dendritic ulcer — treated with topical antiviral (ganciclovir ophthalmic gel or trifluridine drops) and/or oral antivirals
• Stromal keratitis: An immune-mediated inflammation that can cause permanent scarring. Treated with topical corticosteroids (under ophthalmologic supervision only) plus antiviral coverage.
• Recurrent disease: Long-term oral suppressive therapy with acyclovir 400 mg twice daily reduces recurrence of all forms of HSV eye disease by approximately 50% (the landmark Herpetic Eye Disease Study / HEDS trials)

Any eye symptoms in a patient with herpes — pain, redness, light sensitivity, blurred vision, tearing — warrant same-day ophthalmologic evaluation.

• Highest risk: primary HSV acquisition in the third trimester. A woman who acquires genital herpes for the first time near the time of delivery has a 30–50% risk of transmitting HSV to the neonate during vaginal delivery. This is because she has not yet developed protective antibodies. Cesarean delivery is strongly recommended if active lesions or prodromal symptoms are present at the time of labor.
• Lower risk: recurrent genital herpes with known history. A woman with a history of genital herpes before pregnancy who has a recurrence at the time of delivery has a much lower neonatal transmission risk (roughly 1–3% with vaginal delivery through active lesions). She has established antibodies that partially protect the infant. Cesarean delivery is still recommended if active lesions are present at labor onset.
• Lowest risk: known history, no active lesions at delivery. If there are no active lesions or prodromal symptoms when labor begins, vaginal delivery is appropriate.

ACOG (American College of Obstetricians and Gynecologists) recommends suppressive antiviral therapy starting at 36 weeks of gestation for women with a history of genital herpes:

• Acyclovir 400 mg orally three times daily from 36 weeks until delivery
• Valacyclovir 500 mg orally twice daily from 36 weeks until delivery

This approach reduces the likelihood of an outbreak at delivery by approximately 75% and reduces the need for cesarean delivery due to active herpes lesions. Both acyclovir and valacyclovir are considered safe in pregnancy based on extensive registry data showing no increase in birth defects.

Neonatal herpes is rare (estimated 10 per 100,000 live births in the US) but serious. It presents as one of three forms:

• Skin, eyes, and mouth (SEM) disease: The mildest form. Localized vesicles on skin, eyes, or mouth. With prompt IV acyclovir treatment, outcomes are generally good.
• CNS disease: Encephalitis with seizures, lethargy, and poor feeding. Carries significant morbidity even with treatment.
• Disseminated disease: The most severe form, involving multiple organs (liver, lungs, brain). Mortality approaches 30% even with treatment.

Treatment is IV acyclovir 20 mg/kg every 8 hours for 14–21 days, followed by oral suppressive acyclovir for 6 months. Any newborn with vesicles, unexplained sepsis-like illness, seizures, or other concerning symptoms in the first month of life should be evaluated for neonatal herpes and treated empirically while awaiting test results.

• Pritelivir (AIC316)
  A helicase-primase inhibitor with a novel mechanism of action distinct from acyclovir-class drugs. Phase 3 trials are ongoing for immunocompromised patients with acyclovir-resistant HSV (NCT03073967 — NCT03073967 — completed phase 3 for acyclovir-resistant mucocutaneous HSV in immunocompromised; further development ongoing). In a phase 2 trial in immunocompetent adults with genital HSV-2, pritelivir reduced viral shedding by 87% compared to placebo. It represents the first truly new class of anti-HSV drug in decades and may become important for acyclovir-resistant infections and potentially as an alternative to current antivirals.
• Amenamevir (ASP2151)
  Another helicase-primase inhibitor approved in Japan (2017) for the treatment of shingles. Not yet approved in the US or EU. Offers once-daily dosing and is not renally eliminated, which may be advantageous in patients with kidney disease.

• HSV529 (Sanofi Pasteur / NIAID)
  A replication-defective HSV-2 vaccine (deleted for UL5 and UL29 genes) initially developed as a prophylactic vaccine. Phase 1 trial (NCT02571166 — NCT02571166 per guide reference) demonstrated safety and immunogenicity in both HSV-seronegative and HSV-seropositive adults. Further development is ongoing.
• GEN-003 (Genocea Biosciences)
  A protein subunit therapeutic vaccine that showed modest reduction in viral shedding and genital lesion rates in a phase 2 trial. Development was discontinued by Genocea, but the approach informed subsequent therapeutic vaccine efforts.
• mRNA-based vaccines
  Multiple companies (including Moderna) are exploring mRNA vaccine platforms for HSV, leveraging the technology proven successful with COVID-19 vaccines. Moderna’s mRNA-1608 is a trivalent therapeutic HSV-2 vaccine in phase 1/2 trials (NCT06033261 — search ClinicalTrials.gov by “mRNA-1608” for current enrollment). BioNTech is also developing an HSV-2 mRNA vaccine candidate (BNT163).

A preventive herpes vaccine has been a goal of virology for decades. Key developments:

• The challenge: HSV has evolved sophisticated immune evasion mechanisms, and previous vaccine candidates (including GSK’s Simplirix gD2 subunit vaccine and Herpevac Trial for Women) have failed in phase 3 trials despite promising early results. The immune correlates of protection against HSV are not fully understood, making vaccine design difficult.
• Current approaches: Live-attenuated viruses (HSV529, rationally designed deletion mutants), mRNA vaccines, adjuvanted subunit vaccines, and novel viral vector approaches are all in development. The field has been reinvigorated by new understanding of mucosal immunity and tissue-resident memory T cells.
• Timeline: No prophylactic HSV vaccine is likely to reach the market before the late 2020s at the earliest. Several candidates are in early clinical trials.

The most ambitious area of herpes research aims to eliminate the latent virus from nerve cells using gene editing technologies:

• Excision BioTherapeutics (Fred Hutch / Dr. Keith Jerome)
  Using meganuclease gene editing delivered by adeno-associated virus (AAV) vectors to target and destroy latent HSV DNA in sensory ganglia. Preclinical studies in mice have demonstrated elimination of over 90% of latent HSV-1 from trigeminal ganglia and significant reduction in HSV-2 from sacral ganglia. This program remains at the preclinical stage; no human trial is yet registered on ClinicalTrials.gov. It represents one of the closest approaches to a potential true cure currently in development.
• CRISPR-based approaches: Multiple academic groups are exploring CRISPR/Cas9 and base editing to target latent HSV genomes. Challenges include delivering gene editing machinery specifically to latent virus in deep nerve ganglia, achieving sufficient editing efficiency without off-target effects, and the large latent viral DNA reservoir that must be addressed.

Some facts that may help reframe the diagnosis:

• Most adults in the world have at least one herpes virus. HSV-1 alone infects roughly two-thirds of the global population under 50.
• Most people with herpes do not know they have it. You are not unusual — you are simply informed.
• Herpes does not define your health, your worth, or your future relationships.
• Effective treatment exists that dramatically reduces outbreaks and transmission risk.
• People with herpes have fulfilling sex lives, loving relationships, healthy pregnancies, and completely normal life expectancies.
• The stigma associated with genital herpes is largely a historical accident — a product of pharmaceutical marketing in the 1970s-80s that positioned herpes as a serious condition to sell treatments.

• Learn to recognize prodromal symptoms (tingling, itching, burning) and start episodic treatment promptly if not on suppressive therapy
• Keep antiviral medication on hand at home and when traveling
• During outbreaks: keep lesions clean and dry, avoid touching and then touching other body areas, wash hands after any contact with lesions, wear comfortable loose cotton underwear
• Avoid sexual contact during active outbreaks (from first prodromal symptoms until complete healing)
• Common triggers to be aware of: stress, illness, fatigue, sun exposure (for oral HSV — use lip sunscreen), menstruation, friction or trauma to the affected area
• Pain management: cool compresses, over-the-counter pain relief, topical lidocaine for genital lesions, sitz baths

Studies consistently show that the psychological impact of a herpes diagnosis often exceeds the physical impact, particularly for genital herpes. Common emotional reactions include shock, shame, anger, anxiety about future relationships, and depression. These reactions are normal, valid, and usually improve with time and accurate information.

• Individual counseling: A therapist familiar with sexual health issues can help process the diagnosis and develop coping strategies.
• Support groups: The American Sexual Health Association (ASHA) runs the Herpes Resource Center and maintains support resources. Online communities can also help, though quality varies — stick to moderated, fact-based groups.
• Education: Many patients find that learning the facts about herpes — how common it is, how manageable it is, and how low transmission risk can be with precautions — is the single most effective intervention for their emotional distress.
• Time: Most people report that the emotional impact of a herpes diagnosis diminishes significantly within the first year as they gain experience managing it and see that it does not define their lives.

For most of human history, herpes was considered a minor, unremarkable skin condition. The intense stigma surrounding genital herpes is largely a product of the late 20th century:

• Before the 1970s, medical textbooks devoted little attention to genital herpes. It was considered a nuisance, not a crisis.
• The development and marketing of acyclovir in the early 1980s was accompanied by public awareness campaigns that, while well-intentioned, framed herpes as a serious and stigmatized condition. The marketing created the problem that the product then solved.
• Media coverage during this period used alarming language that amplified public fear disproportionate to the actual medical significance of the condition.
• The result is the current cultural environment where cold sores (oral HSV-1) are considered normal, but genital herpes (often the same virus, transmitted to a different location) carries intense stigma. This distinction is medically arbitrary.

• Facts counter stigma. When people learn how common herpes is, how most people acquire it, and how manageable it is, the emotional charge often decreases.
• Language matters. A person “has herpes” — they are not “a herpes patient” or “herpes-positive” as an identity. It is a viral infection, not a character trait.
• Normalize the conversation. The more herpes is discussed matter-of-factly, the less power stigma holds.
• Reject shame. Shame is a social construction, not a medical reality. Having herpes says nothing about a person’s character, hygiene, or judgment.

• Timing: Disclose before sexual contact, ideally in a calm, private setting — not in a moment of passion and not via text (unless the relationship is very new and text is the primary mode of communication).
• Tone: Matter-of-fact and calm. How you present the information strongly influences how the other person receives it. Excessive anxiety or apologizing can inadvertently signal that the situation is worse than it is.
• Information to share: Which virus you have, what you are doing to manage it (suppressive therapy, condoms), what the actual transmission risks are with precautions, and that you wanted to share this so they can make an informed decision.
• Be prepared for questions. The person may need time to process. Offering to share reliable resources (CDC, ASHA) for them to read independently can be helpful.
• A rejection is information, not a verdict. Some people will not be comfortable proceeding, and that is their right. Many others will appreciate the honesty and choose to move forward with the relationship. The majority of disclosed relationships continue.

A serodiscordant couple (one partner has herpes, the other does not) can have a healthy, active sexual relationship with a low risk of transmission using a combination of strategies:

• Daily suppressive antiviral therapy for the positive partner
• Consistent condom use
• Avoiding sexual contact during outbreaks
• Open communication about symptoms and concerns

With all of these measures combined, annual transmission risk for HSV-2 is approximately 1–2%. Many serodiscordant couples maintain these relationships for years without transmission.

• Which herpes virus do I have — HSV-1 or HSV-2? What test confirmed this?
• If the diagnosis is based on blood testing, what was the index value? Do I need confirmatory testing?
• Is this a primary infection or a recurrence?
• Should I start antiviral treatment now?
• What is the expected pattern of recurrences for my virus type and location?
• Should my partner be tested?

• Would daily suppressive therapy be appropriate for me? What are the benefits and costs?
• How do I reduce the risk of transmitting herpes to my partner?
• What should I do at the first sign of an outbreak? How quickly does episodic treatment need to start?
• Are there triggers I can avoid to reduce outbreaks?
• How often do I need follow-up appointments?
• Should I be screened for other STIs?

• I have herpes and I am pregnant (or planning pregnancy). What is the risk to my baby?
• Should I start suppressive therapy before delivery? At what gestational age?
• Under what circumstances would a cesarean delivery be recommended?
• Should my partner be tested if I do not have herpes but my partner does?
• Is breastfeeding safe if I have herpes?

• Is this shingles? What test confirmed it?
• Is it too late for antiviral treatment to help?
• Am I at risk for postherpetic neuralgia? What are the treatment options if pain persists?
• Is my eye involved? Do I need to see an ophthalmologist?
• When can I get Shingrix after this episode?
• Can I spread shingles to others? What precautions should I take?

• Am I eligible for Shingrix? (Am I 50 or older, or immunocompromised and 19 or older?)
• I had Zostavax years ago — do I still need Shingrix?
• What side effects should I expect, and how long do they last?
• When should I get the second dose?
• Is Shingrix covered by my insurance?

After the initial (primary) infection, HSV travels in a retrograde direction along sensory nerve fibers from the site of infection to the sensory ganglia that supply that region:

• Oral HSV-1 travels to the trigeminal ganglion (located at the base of the skull), which supplies sensation to the face, lips, and oral cavity
• Genital HSV-2 (and genital HSV-1) travels to the sacral dorsal root ganglia (S2–S4, in the lower spine), which supply sensation to the genitals, perineum, buttocks, and thighs

Once inside the ganglionic neurons, HSV enters a state of latency: its genome remains as a circular episome (mini-chromosome) within the neuron nucleus, maintaining itself through multiple rounds of cell division without causing active replication or cell death. This latent state is essentially "invisible" to the immune system because no viral proteins are produced at significant levels — there is nothing for the immune system to detect. Antivirals (acyclovir, valacyclovir, famciclovir) work by blocking active viral DNA replication; they have no activity against the latent, non-replicating virus in ganglia. This is why there is no cure: the virus cannot be eliminated from where it hides.

Periodically, the latent virus "wakes up" and undergoes reactivation — resuming active replication and traveling back down the nerve fiber (anterograde direction) to the skin surface. Most reactivation episodes are subclinical (asymptomatic shedding — the virus reaches the skin but causes no visible lesion). A minority of reactivations produce the classic outbreak of vesicles, ulcers, and symptoms.

Triggers for reactivation vary between individuals but commonly include:

• Physical stress and illness: Fever, systemic illness, surgery, physical trauma near the affected dermatome. The reactivation of HSV-1 "cold sores" during a fever is the canonical example — fever was the original namesake for cold sores ("fever blisters").
• Psychological stress: Examinations, major life events, relationship conflict, grief. The neuroimmunological link between psychological stress, cortisol release, and reduced antiviral immune surveillance in ganglionic neurons is well-documented. Patients consistently report stress as a trigger and longitudinal studies confirm the correlation.
• UV light exposure (sunlight): Solar UV triggers HSV-1 reactivation on the lips by damaging local keratinocytes and transiently suppressing local innate immune defenses. Applying SPF 30+ lip protection in sun exposure can reduce cold sore frequency in susceptible individuals.
• Menstruation: Hormonal fluctuations around menstruation trigger genital HSV recurrences in many women, likely through progesterone-mediated immunomodulation in the sacral ganglia. Women who experience consistent menstrual-cycle-timed outbreaks are good candidates for continuous daily suppressive therapy rather than episodic treatment.
• Friction and skin trauma: In genital herpes, prolonged or vigorous sexual activity that creates microtrauma to genital epithelium can trigger a local reactivation. This is thought to involve local inflammatory signals reaching the sacral ganglia and promoting viral reactivation.
• Immunosuppression: Any condition or medication that reduces systemic immune function — HIV, cancer chemotherapy, organ transplant immunosuppressants, high-dose corticosteroids — dramatically increases reactivation frequency and severity by reducing the immune surveillance that normally keeps latent virus suppressed.

Understanding your personal trigger pattern allows you to anticipate high-risk periods and either pre-emptively start episodic antiviral therapy (at the first prodromal sign) or discuss transitioning to continuous suppressive therapy with your provider.

One encouraging biological fact: the immune system does adapt to HSV over time. CD8+ T-cells resident at the sites of prior outbreaks provide ongoing local surveillance that reduces the proportion of reactivation episodes that progress to symptomatic outbreaks. This is why most people find that recurrences become shorter, milder, and less frequent over years — even without medication. Antivirals enhance this natural control; they do not replace it.

Standard STI panels at Planned Parenthood, primary care offices, and most sexual health clinics typically include: HIV, gonorrhea, chlamydia, syphilis (and sometimes hepatitis B and C). They do NOT routinely include herpes blood testing. The US Preventive Services Task Force (USPSTF) in 2016 concluded that there is insufficient evidence to recommend routine herpes screening in asymptomatic adults without active lesions, partly because of concerns about the psychological harms and false-positive test results. This means:

• If you have never had a visible herpes outbreak and have only had "standard STI tests," you have likely never been tested for herpes
• If you have had a lesion, swab-based testing (PCR from the active lesion) is far more reliable than blood testing and is the standard for diagnosis during an active outbreak
• If you want to know your baseline herpes serostatus, you must specifically request HSV type-specific IgG blood testing; not all labs offer it and not all providers will order it without prompting

• The two most widely used type-specific herpes blood tests are HerpeSelect (Focus Diagnostics) and Biokit HSV-2 Rapid Test. Both measure IgG antibodies to type-specific glycoproteins (gG-1 for HSV-1, gG-2 for HSV-2).
• Results are reported as an "index value." For HSV-2 HerpeSelect: <0.9 = negative; 0.9–3.5 = equivocal/low positive (high false-positive rate in this range, particularly in low-prevalence populations); >3.5 = true positive (very high specificity). A value of 1.1–3.5 should be confirmed with a different test (Western blot, the gold standard) before a definitive diagnosis is made.
• The Western blot, available through the University of Washington Virology Lab (UW Medicine), is the gold standard for confirming ambiguous HSV serology. It requires a physician order and laboratory submission; results take 1–2 weeks. For anyone with a low-positive IgG index value (1.1–3.5) who is making major life decisions based on the result, Western blot confirmation is strongly recommended.
• IgM testing for herpes is NOT recommended: it cannot reliably distinguish primary from recurrent infection, is frequently falsely positive in people with other viral infections, and is not type-specific. Disregard IgM results for herpes; rely on type-specific IgG and/or swab PCR.

• Adjustment over time: Longitudinal studies of people with HSV-2 show that quality of life at 12 months is substantially better than at 1 month post-diagnosis for most patients. The initial crisis of diagnosis (grief, anger, shame, fear about relationships) typically gives way to adaptation as the person accumulates experience managing the condition. Recurrences become less frightening when the patient understands what to expect and knows how to manage them.
• Predictors of poor adjustment: More frequent recurrences, history of depression or anxiety prior to diagnosis, lack of social support, relationship conflict around the diagnosis, and strong internalized stigma are all associated with persistent quality-of-life impairment. Early engagement with a therapist familiar with sexual health and chronic illness can interrupt poor adjustment trajectories.
• Recurrence frequency and its trajectory: In HSV-2, recurrences peak in the first 6–12 months after primary infection and then gradually decrease on average over years. Some individuals with frequent early recurrences find that by years 3–5, recurrences have become infrequent enough that suppressive therapy is no longer needed. This is not guaranteed, but it is the natural history in many patients.
• Chronic pain and neuralgia: A small subset of HSV-2 patients develop chronic genital pain or neuralgia that persists between outbreaks. This is distinct from postherpetic neuralgia (which follows shingles) but similarly challenging to treat. Management involves gabapentinoids, tricyclic antidepressants, topical lidocaine, and pain psychology. Referral to a vulvodynia or chronic pelvic pain specialist may be appropriate for women with chronic genital pain syndromes.
• Support communities: Online communities specifically for people with herpes — Herpes Opportunity, ASHA support group directory (ashasexualhealth.org), and the Planned Parenthood herpes resources — offer peer connection that normalizes the diagnosis and provides practical lived-experience wisdom that clinical encounters rarely offer.

The ZOE-50 and ZOE-70 trials (published in NEJM 2015 and 2016) established Shingrix efficacy across age groups:

• Adults 50–59: 97% efficacy against shingles
• Adults 60–69: 97% efficacy
• Adults 70–79: 91% efficacy
• Adults 80+: 89% efficacy
• Protection against postherpetic neuralgia (PHN): 91% overall reduction
• Duration of protection: maintained above 85% through at least 7 years of follow-up in trial data; immunological studies suggest durability extends beyond 10 years

ACIP recommendations for Shingrix (2022):

• Adults aged 50 and older: routine vaccination recommended (2 doses, 2–6 months apart)
• Adults 19 and older who are or will be immunodeficient or immunosuppressed (due to disease or therapy): routine vaccination recommended — earlier than the general 50+ recommendation
• Previously vaccinated with Zostavax: re-vaccinate with Shingrix (far superior efficacy); wait at least 8 weeks after Zostavax
• History of prior shingles: still vaccinate with Shingrix to prevent recurrence (recurrence risk is approximately 5% without vaccination)

• Shingrix is a two-dose intramuscular injection series, given 2–6 months apart (can be given 1–2 months apart in immunocompromised patients who may have narrower vaccination windows)
• Reactogenicity (side effects) is notably higher with Shingrix than most adult vaccines: Approximately 78% of recipients experience local injection site reactions (pain, redness, swelling) and approximately 27% experience systemic reactions (fatigue, headache, muscle pain, shivering, fever) lasting 1–3 days. These are signs of a robust immune response, not infection. Planning to schedule the vaccine when you can take 1–2 days off if needed is reasonable.
• Shingrix contains no live virus and cannot cause shingles; it is safe in immunocompromised individuals (unlike Zostavax, which was live-attenuated and contraindicated in severely immunocompromised patients)
• Shingrix is NOT indicated for treatment of active shingles or prevention of initial chickenpox (Varivax, the varicella vaccine, serves that purpose in children and VZV-naive adults)
• Cost and coverage: CDC Adult Immunization Schedule includes Shingrix; Medicare Part D, most commercial insurance plans, and Medicaid cover Shingrix for eligible adults with appropriate age/indication criteria

• Both HSV-1 and HSV-2 cause genital infections in MSM; HSV-1 accounts for an increasing proportion of genital herpes in MSM, largely driven by receptive oral sex
• Rectal herpes (proctitis) occurs in receptive anal sexual contacts; presents as anorectal pain, discharge, tenesmus, and sacral radiculopathy (causing urinary symptoms and paresthesias in the buttocks and thighs) from the S2–S4 dermatomes. Diagnosis by anal/rectal swab PCR.
• Herpetic pharyngitis occurs in insertive oral sex; presents as sore throat with vesicles and ulcers on the palate and posterior pharynx, often confused with streptococcal pharyngitis. HSV PCR throat swab distinguishes herpes pharyngitis from strep.
• Disseminated or unusually severe herpes infections occur significantly more commonly in HIV-positive MSM with low CD4 counts; see the immunocompromised section for details on management
• MSM using PrEP (pre-exposure prophylaxis for HIV prevention) have substantially lower rates of HIV acquisition but continued high rates of STI acquisition including herpes; PrEP clinics are important venues for herpes screening, counseling, and suppressive therapy prescription

• Anal HSV and HIV interaction: Anal HSV ulceration significantly increases HIV acquisition and transmission risk (both by concentrating HIV target cells at the mucosal surface and by providing viral entry points). MSM with active anal herpes who are HIV-negative should be urgently offered HIV PrEP. MSM with anal herpes who are HIV-positive should ensure optimal ART suppression and consider daily HSV suppression to reduce co-amplification of both viruses.
• Distinguishing HSV proctitis from other causes: Rectal STIs in MSM include gonorrhea, chlamydia, syphilis, lymphogranuloma venereum (LGV), and herpes. Each has somewhat different clinical features but overlap is common; comprehensive STI panel (including HSV PCR swab, rectal gonorrhea/chlamydia NAAT, LGV chlamydia reflex testing, syphilis serology) is standard for acute proctitis workup in MSM.
• Suppressive therapy for MSM: Daily suppressive valacyclovir is particularly valuable in MSM with HSV-2 and multiple partners, given the dual HIV and transmission-reduction benefits. Discussion of suppressive therapy should be integrated into routine PrEP/STI care visits.
• Resources: GLMA (GLMA: Health Professionals Advancing LGBTQ+ Equality), community health centers with dedicated MSM STI programs (e.g., Callen-Lorde in New York, Fenway Health in Boston, Lyon-Martin in San Francisco), and AIDSVu.org for HIV/STI resources in specific communities.

Studies of high school and collegiate wrestlers in the US show herpes gladiatorum prevalence of 2–8% among active wrestlers, with higher rates in older athletes with longer competitive careers. Transmission occurs through contact between an active (or asymptomatically shedding) lesion and abraded skin, mucosa, or open skin cuts from the sport. Risk factors include:

• Skin abrasions from mat contact ("mat burns") that create entry portals for the virus
• Prolonged face-to-face and skin-to-skin contact inherent to wrestling and grappling sports
• Head and neck are the most common affected areas in wrestlers (from head-to-head contact positions)
• Shared towels, headgear, and equipment (though direct contact is the main route)

• Diagnosis: Vesicular or ulcerative lesions in typical skin distribution for wrestling contact (face, neck, shoulders, arms). PCR from lesion is the most sensitive test.
• NCAA and high school exclusion rules: Active lesions disqualify a wrestler from competition. The NCAA Wrestling Rules and Interpretations specify that wrestlers with active herpes gladiatorum outbreaks may not compete; return is permitted only when lesions are fully crusted and dried, with documentation of at least 120 hours of antiviral therapy. Coaches and athletic trainers should know these rules.
• Daily suppressive therapy for competitive athletes: Valacyclovir 500–1,000 mg daily during the wrestling season is widely used in Division I programs to reduce outbreak frequency and shedding during competition periods. This is off-label but consistent with standard herpes suppression practice.
• Prevention beyond antivirals: Prompt showering after contact with soap and water; inspection of self and opponents for lesions before practice (active lesions should prompt removal from contact drill); skin barrier protectants over minor abrasions during contact; no sharing of towels or face equipment.

First genital herpes episode (primary infection): More severe and prolonged than recurrences; early treatment significantly reduces duration and symptom severity. Start treatment as soon as possible after symptom onset — ideally within 48–72 hours.

• Acyclovir 400 mg three times daily × 7–10 days or 200 mg five times daily × 7–10 days
• Valacyclovir 1 g twice daily × 7–10 days
• Famciclovir 250 mg three times daily × 7–10 days

Recurrent genital herpes episodes: Shorter course; treatment reduces duration and severity but benefits are modest compared to the first episode. Only useful if started within 48–72 hours of prodrome or lesion onset.

• Acyclovir 800 mg three times daily × 2 days (short course) or 400 mg three times daily × 5 days
• Valacyclovir 500 mg twice daily × 3 days (or 1 g once daily × 5 days)
• Famciclovir 1 g twice daily × 1 day (single-day regimen); or 500 mg once, then 250 mg twice daily × 2 days

Oral herpes (cold sores, HSV-1): Most cold sores are self-limiting; antivirals modestly shorten duration if started at prodrome (tingling/burning before the sore appears). Valacyclovir 2 g twice daily × 1 day is FDA-approved for oral herpes recurrences in adults.

Suppressive therapy (daily antiviral dosing) is appropriate for:

• Patients with 6 or more recurrences per year
• Patients who find outbreaks significantly impair quality of life or relationships, regardless of frequency
• Serodiscordant couples who want to reduce transmission risk to the uninfected partner
• Patients with immunocompromising conditions
• Pregnancy (36 weeks until delivery to suppress virus near delivery)

Dosing for suppressive therapy:

• Valacyclovir 500 mg once daily (for patients with ≤9 outbreaks/year); 1 g once daily if more frequent
• Acyclovir 400 mg twice daily (equally effective but requires twice-daily dosing; often better adherence with valacyclovir once-daily)
• Famciclovir 250 mg twice daily

How long to continue suppressive therapy? There is no defined endpoint. Most experts recommend reassessing annually — some patients find that suppressive therapy significantly reduces frequency and are satisfied to continue indefinitely; others try stopping after 1–2 years and find recurrences have naturally become infrequent with time. Herpes naturally decreases in recurrence frequency over years in most people.

Safety of long-term suppressive therapy: Acyclovir and valacyclovir have been used continuously for more than 6 years in clinical trials with an excellent safety profile. No evidence of cumulative toxicity or viral resistance in immunocompetent patients on suppressive doses (resistance occurs primarily in severely immunocompromised patients on high-dose IV therapy).

US law varies by state regarding legal duties to disclose STIs. In some states, knowingly transmitting herpes without disclosure to the partner can constitute criminal exposure to an STI. Consult your state laws if unsure; organizations like the National Herpes Resource Center (ASHA) publish state-by-state guidance. From an ethical standpoint, most ethicists and public health practitioners support disclosure before sexual contact because it respects partner autonomy and allows informed consent to the risk of transmission.

• Choose the right moment: Not in the heat of the moment, not via text for the first time. A calm, private setting before sexual contact occurs. You control the timing; there is no obligation to disclose on a first date, but disclosure should happen before any sexual activity that carries transmission risk.
• Prepare key facts in advance: Understand your own situation (HSV-1 vs HSV-2, frequency of outbreaks, whether you take suppressive therapy) so you can answer questions confidently. Correct common myths proactively: herpes is not cancer-linked (that is HPV), herpes does not affect fertility or general health, herpes is not reliably detected on standard STI panels (partners who want testing need to specifically request HSV IgG type-specific testing).
• Expect variable reactions: Some partners will be understanding; others will need time to process; some will choose not to continue the relationship. All of these are reasonable responses to information that genuinely changes the context of a relationship. Their reaction is not within your control; your honesty is.
• Support resources for disclosure: ASHA HerpesLine (1-800-230-6039) provides counseling. Online communities (Herpes Opportunity, r/Herpes on Reddit) include thousands of people who have navigated disclosure and can provide peer perspective. For anxiety around disclosure, a therapist familiar with sexual health issues can help develop disclosure language and process related anxiety.
• Partner testing: Encourage partners to get HSV type-specific IgG serology testing (not routine STI panels, which typically exclude herpes). Knowing their baseline status is important context: a partner who is already HSV-2 IgG positive faces no additional transmission risk from a partner with genital HSV-2.

The majority of herpes transmission (estimated 70–80% of cases) occurs when neither partner knows an active outbreak is happening. This is because of asymptomatic viral shedding — periods when the virus replicates and is present on genital skin without causing any visible lesion or symptom. Key facts:

• People with genital HSV-2 shed virus asymptomatically on approximately 10–20% of days in the absence of suppressive therapy
• Shedding episodes typically last less than 12 hours and occur unpredictably — there is no reliable way to predict when shedding is happening without daily PCR testing, which is not clinically practical
• Shedding is most frequent in the first year after primary infection and in the first 6 months following any symptomatic recurrence; it decreases but persists indefinitely even years after primary infection
• Shedding rates are lower for HSV-1 genital infection (5–8% of days) and for oral HSV-1 than for genital HSV-2
• Suppressive therapy (daily valacyclovir or acyclovir) reduces shedding by approximately 80% — from shedding on ~15% of days to ~3% of days — but does not eliminate it completely

The landmark Valacyclovir Transmission Study (Corey et al., NEJM 2004) provides the most reliable transmission probability data:

• In heterosexual serodiscordant couples (one partner HSV-2 positive, one negative) with NO intervention: approximately 10% annual transmission rate from male to female, approximately 4% from female to male
• Condoms alone (consistent male condom use): reduced male-to-female transmission to approximately 4%, female-to-male to approximately 2%
• Valacyclovir suppressive therapy alone (500 mg/day in source partner): reduced transmission by 48% (female partners: from 3.6% to 1.9% per year)
• Condoms + suppressive therapy combined: further reduction; estimated <1% annual risk in most serodiscordant couples

These numbers convey that herpes transmission is not inevitable and that combining multiple prevention strategies substantially reduces risk — while also conveying that transmission can still occur even with precautions. These are annual rates, not per-act rates: the per-act transmission probability from a single sexual contact is much lower.

Per-act transmission from vaginal intercourse with no protection: approximately 0.4–0.6% per act (HSV-2 male-to-female), 0.1–0.2% (female-to-male). These low per-act rates explain why couples can have sex many times before transmission occurs, and also why transmission is possible even after many protected acts.

Male latex condoms reduce, but do not eliminate, herpes transmission risk. The key limitation is skin-to-skin transmission: herpes is shed from genital and surrounding skin surfaces that condoms do not cover (perineum, scrotum, inner thighs, buttocks). This "shedding geography" means that even perfect condom use provides only partial protection against herpes, unlike HIV or gonorrhea where transmission is primarily via the mucosal route covered by the condom.

• Female condoms (internal condoms) cover more genital skin area than male condoms and may provide marginally better protection, but data are limited
• Dental dams (latex oral barriers) reduce oro-genital transmission risk during oral sex
• Condoms + suppressive therapy together provide the greatest risk reduction currently available outside of abstinence

Patients undergoing chemotherapy, targeted therapy, or stem cell transplant for cancer are at high risk of serious herpes virus reactivation. Prophylactic antiviral therapy (acyclovir or valacyclovir) during high-risk immunosuppression periods is standard of care in oncology.

• HSV reactivation can cause esophagitis (pain with swallowing, often misattributed to chemotherapy mucositis) or encephalitis in severely immunosuppressed patients
• VZV reactivation (shingles) can be severe, disseminated, and multi-dermatome in cancer patients — requires IV acyclovir for disseminated or severe disease
• Inform your oncologist about your herpes history before starting immunosuppressive therapy; ensure prophylactic antivirals are part of your cancer care plan
• Shingrix vaccination is recommended before starting immunosuppressive therapy when feasible (timing depends on the specific treatment)

Many autoimmune conditions (lupus, rheumatoid arthritis, inflammatory bowel disease, MS) require immunosuppressive medications (prednisone, azathioprine, mycophenolate, methotrexate, TNF inhibitors, JAK inhibitors, biologics). These medications can reactivate HSV and VZV. Key points:

• Herpes zoster incidence is 2–8 fold higher in patients on biologic therapies (particularly anti-TNF agents and JAK inhibitors) than in the general population. JAK inhibitors carry the highest VZV reactivation risk among commonly used biologics.
• Shingrix vaccination is recommended (and generally safe) for patients on most biologic therapies. The vaccination should ideally be completed before starting biologics where possible. Timing of Shingrix with respect to specific immunosuppressants should be discussed with the prescribing rheumatologist or gastroenterologist.
• Genital HSV outbreaks may be more frequent or prolonged on immunosuppressive therapy. Discuss whether suppressive therapy is indicated.
• Some JAK inhibitors (tofacitinib, baricitinib) now have FDA-labeled warnings about herpes zoster risk; some prescribing guidelines recommend antiviral prophylaxis during JAK inhibitor therapy.

Acyclovir, valacyclovir, and famciclovir are all renally excreted and require dose adjustment in patients with impaired kidney function (eGFR <50 mL/min/1.73m²). Failure to adjust doses in renal impairment can cause nephrotoxicity or, with high-dose IV acyclovir, neurotoxicity (confusion, tremor, somnolence — "acyclovir encephalopathy"). Key principles:

• Always inform your prescriber of your kidney function when receiving antiviral prescriptions
• For IV acyclovir: adequate hydration before and during infusion is essential; infuse slowly (over at least 1 hour)
• Patients on dialysis require very specific dosing schedules; nephrology or pharmacy consultation is advisable
• Probenecid (sometimes used for gout) and cimetidine (H2 blocker) reduce renal acyclovir clearance and can cause drug accumulation; inform your provider if you take either

• Fever with severe headache and stiff neck (meningismus): This triad raises concern for herpes meningitis (usually HSV-2, generally benign and self-limiting) or, more seriously, herpes encephalitis (HSV-1, neurological emergency). Do not wait for a routine appointment.
• Confusion, altered consciousness, seizures, or personality change: Possible herpes encephalitis. Call 911. This is a neurological emergency requiring IV acyclovir.
• Severe eye pain, redness, photophobia, or vision change: Possible HSV keratitis or herpes zoster ophthalmicus. Same-day ophthalmology evaluation is required; do not wait overnight.
• Genital herpes pain so severe you cannot urinate: Urinary retention from severe genital herpes neurological involvement (sacral radiculopathy) can cause acute urinary retention requiring catheterization. Go to the ED.
• Immunocompromised patient with any active herpes outbreak: Significantly immunocompromised patients (CD4 <200, transplant recipient within 6 months, active leukemia therapy) with active herpes should be evaluated more urgently than immunocompetent patients and may need IV antiviral therapy.
• Herpes outbreak in a newborn (<28 days): This is a pediatric emergency. Any vesicular rash, fever, or neurological signs in a newborn from a mother with herpes requires immediate neonatal evaluation.

• Outbreaks that are not healing after 10–14 days on antiviral therapy (consider resistance testing)
• Unusually frequent outbreaks (>6/year) not controlled with episodic therapy (consider suppressive therapy)
• First diagnosis of genital herpes in pregnancy (urgent but not emergency)
• Signs of a possible secondary bacterial infection superimposed on a herpes sore: increasing redness, warmth, swelling, pus, or worsening pain after 5–7 days of antiviral treatment (bacterial superinfection is uncommon but can occur)
• Active shingles rash (same-day or next-day evaluation is ideal to start antivirals within the 72-hour window for maximum benefit)
• Questions about antiviral prescription, suppressive therapy, or transmission prevention

Postherpetic neuralgia (PHN) is the most common complication of shingles — a painful, burning, or electric-shock-like pain that persists in the area of the shingles rash after the rash itself has healed. PHN affects approximately 10–15% of all shingles patients but rises steeply with age: approximately 40% of patients over 60 who get shingles develop PHN, and it may last months to years. PHN is one of the major reasons that shingles vaccination is strongly recommended for adults 50+, as vaccination dramatically reduces PHN incidence.

PHN pain can be severe and is frequently undertreated. Evidence-based treatments for PHN include:

• Gabapentin (Neurontin) or pregabalin (Lyrica): First-line agents for PHN per FDA approval. Dose gradually to effective or maximally tolerated dose; watch for dizziness and sedation.
• Tricyclic antidepressants (nortriptyline, amitriptyline): Effective neuropathic pain agents at low doses; useful especially for concurrent sleep disturbance. Monitor for anticholinergic effects, particularly in elderly patients.
• Lidocaine 5% topical patch (Lidoderm): FDA-approved for PHN; applied to the painful area for 12 hours on, 12 hours off. Minimal systemic absorption; well tolerated.
• Capsaicin 8% patch (Qutenza): Applied in a clinical setting, provides 3 months of pain relief after a single 60-minute application. Initial burning during application is a barrier.

Primary HSV-1 infection in young children (typically ages 1–5) causes herpetic gingivostomatitis — a painful mouth infection with vesicles on the gums, tongue, inner cheeks, and lip borders, accompanied by fever, irritability, drooling, and refusal to eat or drink. It is often the sickest a young child looks for what is ultimately a self-limited viral illness. Duration is 7–14 days. Management focuses on:

• Pain control: liquid acetaminophen or ibuprofen; magic mouthwash (a mixture of liquid antacid, diphenhydramine, and sometimes viscous lidocaine) for topical pain relief — available by prescription
• Hydration: offer cold fluids, popsicles, ice cream; avoid acidic or salty foods that worsen pain. Watch for dehydration (dry mouth, no urination for >8 hours) — if unable to maintain oral hydration, IV fluids may be needed
• Oral acyclovir: if started within 72 hours of symptom onset, acyclovir suspension (15 mg/kg, 5 times daily for 7 days) shortens illness duration by 2–4 days — a meaningful benefit for a severely symptomatic child

A child with active herpetic gingivostomatitis should be kept home from daycare or school while sores are weeping, to minimize transmission to other children, and definitely kept away from immunocompromised individuals and newborns.

After the primary infection, the child carries HSV-1 latently and may have recurrent cold sores (orolabial herpes) for the rest of their life. Recurrent cold sores are smaller, less severe, and more localized than the primary infection. School policies on children with cold sores vary: most do not require exclusion for a single cold sore on the lip, as this is extremely common. Children should be taught not to touch sores and wash hands after any contact. They should not share drinks, food utensils, or lip products.

The main concern in school settings is contact with immunocompromised classmates (those undergoing chemotherapy, taking immunosuppressive medications, or with HIV). A child with an active cold sore should avoid close contact (kissing, sharing food) with immunocompromised schoolmates and should definitely not visit immunocompromised individuals in medical settings.

Herpetic whitlow: A child with active gingivostomatitis who sucks their thumb or fingers can inoculate HSV-1 onto their fingers, causing herpetic whitlow (a painful HSV infection of the finger). Herpetic whitlow in healthcare workers who contact patient oral secretions without gloves was historically common before universal precautions. Treat with oral antiviral; do not incise (drainage does not help and can spread infection).

HSE is caused almost exclusively by HSV-1 (not HSV-2 in adults) and occurs through two mechanisms: primary infection in seronegative individuals (accounting for approximately one-third of cases) and reactivation in seropositive individuals (the majority of cases). Counterintuitively, most people who develop HSE do not have a prior history of oral herpes lesions — HSV-1 reactivation occurs in the brain (specifically in the temporal lobes, which are the primary sites of HSV-1 latency in trigeminal ganglia) in ways that produce encephalitis even in immunocompetent individuals. HSE is not more common in immunocompromised patients than in immunocompetent ones — unlike most other opportunistic infections, HSE strikes across the immune spectrum. Annual incidence is approximately 1–3 per million population.

HSE classically presents with a prodrome of fever, headache, and behavioral changes over 2–4 days, followed by:

• Confusion and altered consciousness (ranging from disorientation to coma)
• Personality changes, aggression, or bizarre behavior (from temporal lobe involvement)
• Focal neurological signs: aphasia (speech difficulty), memory impairment (dense amnesia), visual field defects
• Seizures (focal or generalized) in approximately 60–80% of cases
• Fever is usually (but not always) present

Diagnosis requires:

• MRI brain: Characteristic bilateral temporal lobe signal changes (T2/FLAIR hyperintensity, restricted diffusion) in 90%+ of cases. MRI is much more sensitive than CT. However, early in the course (<48–72 hours), MRI may be normal — a normal early MRI does not exclude HSE.
• CSF HSV PCR: Lumbar puncture with CSF sent for HSV-1 and HSV-2 PCR. Sensitivity is approximately 96% after day 3 of illness; sensitivity is lower in the first 48 hours. A negative HSV PCR in the first 24–48 hours of illness does not rule out HSE; repeat LP at 72–96 hours is warranted if suspicion remains high.
• EEG: Shows periodic lateralized epileptiform discharges (PLEDs) over the temporal regions in approximately 75% of HSE cases. EEG is also critical for monitoring for subclinical seizures.

Critical principle: Start IV acyclovir empirically while awaiting diagnostic confirmation. The risk of a 10-day course of acyclovir in a patient who turns out not to have HSE is negligible (mild renal monitoring required). The risk of delaying treatment in a patient who does have HSE is devastating and irreversible. Acyclovir is started at 10 mg/kg IV every 8 hours for 14–21 days when HSE is suspected.

HSV poses unique challenges to vaccine development:

• Immune evasion: HSV has evolved sophisticated mechanisms to evade both innate and adaptive immunity. It encodes proteins that interfere with antigen presentation (downregulation of MHC class I molecules), complement activation, and interferon signaling. Natural infection with HSV does not provide sterilizing immunity — people with HSV can be reinfected with different strains. A vaccine would need to be more effective than natural infection at inducing protective immunity.
• Latency: HSV establishes permanent latency in sensory neurons. Even if a vaccine prevented primary infection, it would not clear existing latent infection. The target for a therapeutic vaccine (to reduce recurrences in already-infected people) is different from the target for a preventive vaccine.
• Previous vaccine failures: Multiple candidate vaccines have failed in clinical trials. The most disappointing was the Herpevac trial (gD2 protein + adjuvant, GlaxoSmithKline), which showed approximately 73% protection against HSV-1 genital disease in HSV-seronegative women but ZERO protection against HSV-2. Subsequent analysis suggested the vaccine induced an antibody response but not the T-cell response needed to prevent HSV-2 infection.

The current HSV vaccine pipeline has shifted toward candidates that prioritize cellular immunity (CD4+ and CD8+ T-cells) rather than antibody responses alone, based on evidence that T-cell immunity is the primary correlate of protection against HSV:

• mRNA-based HSV vaccines (Moderna, BioNTech): Both companies have HSV-2 mRNA vaccine programs in early-phase clinical trials, applying mRNA vaccine technology similar to that used for COVID-19. Moderna’s mRNA-1608 entered Phase 1 trials. BioNTech’s HSV program is in early development. Results from Phase 1/2 immunogenicity and safety studies are expected in 2025–2026. Whether mRNA-based vaccines will overcome the HSV immune evasion problem remains to be seen.
• Live-attenuated HSV vaccines: The Bhatt lab (previously at Stanford, now at University of Cincinnati) has developed a live-attenuated HSV-2 vaccine strain with UL5 deletion (HSV529) that cannot reactivate from latency. This candidate showed strong immunogenicity in initial human studies. Larger efficacy trials are under discussion.
• Therapeutic vaccines: For people already infected with HSV, therapeutic vaccines designed to reduce recurrence frequency are also in development. These aim to boost the T-cell response in latently infected individuals to keep viral reactivation suppressed.

No herpes vaccine is expected to be commercially available before 2028–2030 at the earliest, and some candidates may not reach licensure at all. Clinical trial enrollment sites and updates can be tracked at clinicaltrials.gov searching "herpes simplex vaccine."

Herpes is among the most common infections worldwide. WHO 2020 estimates:

• HSV-1: 3.7 billion people under age 50 (67% of the global population under 50) infected, primarily orolabially. HSV-1 genital infection is increasing in high-income countries, now accounting for 30–50% of new genital herpes cases in some European and North American studies.
• HSV-2: 491 million people aged 15–49 (13% of the global adult population), with highest prevalence in sub-Saharan Africa (31.5% of women, 22.8% of men) and lowest in Europe and East Asia.
• VZV (varicella/shingles): nearly universal infection with primary varicella (chickenpox) before vaccination programs; universal VZV reactivation risk throughout lifetime with age-related and immune status-related risk escalation.

International access to antivirals: acyclovir (off-patent since the 1990s) is widely available and affordable globally, including in low-income countries. Valacyclovir generic is available but less universally affordable. Famciclovir generic has variable access. Access to type-specific serology varies significantly by country. In many low-income countries, clinical diagnosis without laboratory confirmation remains standard.

HSV-2 infection significantly increases the risk of acquiring HIV if exposed. The mechanisms are multiple: genital ulcers from HSV-2 outbreaks disrupt the mucosal barrier, providing a direct entry portal for HIV. Sub-clinical HSV-2 reactivation without visible ulcers causes mucosal inflammation with increased concentrations of CD4+ T-cells (HIV’s primary target) in the genital tract. Meta-analyses have estimated that HSV-2 infection increases HIV acquisition risk by 2–4 fold per sexual exposure. Given the extraordinarily high global prevalence of HSV-2 (approximately 491 million people aged 15–49 globally per WHO 2016 data), this interaction has significant implications for HIV epidemiology, particularly in sub-Saharan Africa where both infections are highly prevalent.

Trials of HSV suppressive therapy (acyclovir) as an HIV prevention strategy in HSV-2-positive HIV-negative individuals did not demonstrate HIV acquisition risk reduction — even though they successfully suppressed HSV shedding. This surprising finding (the HPTN 039 trial and Partners in Prevention HSV/HIV trial) suggests that the HIV-risk relationship is not primarily driven by lesion-associated mucosal breaches, but by deeper immune cell trafficking changes that persist even when clinical manifestations are suppressed. This remains an active area of investigation.

In people living with HIV (PLWH), HSV infections are more frequent, more severe, and sometimes more atypical. Management principles specific to PLWH with HSV include:

• Universal suppressive therapy for HSV-2 PLWH: Most HIV guidelines recommend suppressive acyclovir or valacyclovir for all HIV-positive patients with HSV-2, regardless of CD4 count, because of the high frequency of recurrences and sub-clinical shedding. This also helps reduce the theoretical risk of HSV-driven HIV viral transcription (HSV activates HIV LTR promoter regions in latently infected cells).
• Higher antiviral doses: Recommended treatment doses for active HSV episodes in PLWH are higher than in immunocompetent patients: valacyclovir 1 g twice daily (vs. 500 mg twice daily) or acyclovir 400 mg three times daily (vs. twice daily) for genital HSV.
• Watch for acyclovir resistance: With cumulative acyclovir exposure in immunocompromised patients, thymidine kinase-deficient HSV mutants can emerge. Clinical suspicion: persistent or worsening HSV lesions despite adequate acyclovir or valacyclovir dosing. Confirm with HSV TK gene sequencing. Treat with IV foscarnet (acyclovir-resistant HSV of all types is typically foscarnet-sensitive).
• Antiretroviral therapy and CD4 recovery: Effective antiretroviral therapy (ART) with CD4 count recovery substantially reduces HSV recurrence frequency in HIV-positive patients. This is another reason to ensure optimal HIV treatment as part of comprehensive HSV management.

• "Herpes is a serious disease that will damage my health long-term." For most immunocompetent adults, herpes is a manageable skin condition with a nuisance impact rather than a life-threatening or organ-damaging disease. The main exception is neonatal herpes and herpes in severely immunocompromised patients. A healthy adult with herpes has a normal life expectancy and can lead a fully normal life.
• "Herpes causes cancer." This is a specific and important misconception. HSV (herpes simplex virus) is NOT associated with cervical cancer or other cancers. Human Papillomavirus (HPV) is the cause of cervical, anal, oropharyngeal, and genital cancers — HPV is a completely different virus from herpes, despite both being STIs. Having herpes does not increase your risk of cancer. The confusion between HPV and HSV is extremely common and causes unnecessary fear.
• "If I have herpes, I must have had many sexual partners or been careless." Herpes is extraordinarily common — HSV-1 is present in roughly two-thirds of adults under 50 worldwide; HSV-2 in about 11% of adults in the US. Given that most people with HSV do not know they are infected and can transmit asymptomatically, you can acquire herpes from any partner who does not disclose because they genuinely do not know. A herpes diagnosis says nothing about your character, judgment, or sexual history.
• "Condoms provide complete protection against herpes." Condoms significantly reduce but do not eliminate herpes transmission risk, because the virus can be present on skin not covered by the condom (the perianal area, scrotum, upper thighs). Condoms are an important risk-reduction strategy but should be understood as risk-reduction, not elimination.
• "Herpes can be transmitted through toilet seats, towels, or hot tubs." HSV does not survive for significant time on inanimate surfaces at room temperature. Transmission requires direct mucosal or skin-to-skin contact with an infected area shedding virus. Casual contact does not transmit genital herpes.

Research consistently shows that the psychological impact of a herpes diagnosis — anxiety, depression, shame, relationship fears, and reduced self-esteem — often exceeds the physical impact. A 2019 systematic review found that 30–50% of people with genital herpes reported significant psychological distress in the period after diagnosis, with many reporting impacts on sexual relationships, self-image, and quality of life. These impacts are not trivial and deserve the same attention as the physical management of the condition.

Signs that additional support may be beneficial:

• Persistent avoidance of all romantic or sexual relationships out of fear of disclosure or transmission
• Ongoing shame, self-blame, or depression that does not improve with time and education
• Intrusive thoughts or anxiety about herpes that interfere with work, social activities, or daily function
• Significant relationship conflict or breakdown specifically related to the diagnosis

Cognitive behavioral therapy (CBT) adapted for chronic illness and sexual health concerns is effective for herpes-related psychological distress. Sexual health counselors and therapists specializing in STI-related concerns are available in many areas. The American Sexual Health Association (ASHA, ashasexualhealth.org) provides a directory of sexual health professionals and has a helpline. Peer support groups — including online communities — can reduce isolation and normalize the experience of living with herpes.

Most people with recurrent herpes learn to recognize a prodrome — warning symptoms that precede the visible outbreak by 12–48 hours. Common prodromal symptoms include tingling, burning, itching, or shooting pain in the area where the outbreak will appear, and sometimes flu-like symptoms (fatigue, mild swollen lymph nodes) with primary infections. Starting antiviral therapy at the first sign of prodrome (rather than waiting for the blister to appear) is the most effective timing for episodic treatment — it shortens both the duration of the outbreak and the severity of symptoms. Keeping a small supply of your episodic antiviral medication at home means you can start treatment immediately without waiting for a prescription refill.

• Cool compresses or ice packs: Applied intermittently to the affected area can reduce pain and swelling. Wrap ice in a cloth; do not apply ice directly to skin.
• Warm sitz baths: For genital outbreaks, a shallow warm bath (sitz bath) 2–3 times daily can soothe pain and help keep the area clean. Dry gently (or use a hair dryer on the lowest setting) after bathing.
• Loose, breathable clothing: Cotton underwear and loose-fitting clothing reduce friction and allow air circulation, which speeds healing. Avoid tight synthetic fabrics during an active outbreak.
• Pain management: Over-the-counter analgesics (ibuprofen, acetaminophen) are effective for outbreak-related pain. For severe genital herpes pain (particularly during primary infections, where walking may be difficult), topical lidocaine gel applied before urination can significantly reduce burning. Ask your provider for a prescription if needed.
• Keeping the area clean and dry: Gently wash with mild soap and water; avoid scrubbing or using alcohol-based products on active sores.
• Avoiding sexual contact: Active lesions are the highest-risk period for transmission. Avoid sexual contact from the start of prodromal symptoms until 48 hours after complete lesion healing (complete re-epithelialization). Condoms do not fully cover all lesion areas and do not eliminate risk during active outbreaks.

Many people with herpes identify patterns in what precipitates their outbreaks. Common triggers include:

• Physical or emotional stress: Stress activates the hypothalamic-pituitary-adrenal axis and suppresses cellular immunity, which normally keeps HSV latent. Major life stressors (job loss, grief, relationship crises) often precede outbreaks in people who notice a pattern.
• Illness or fever: "Cold sores" (orolabial HSV-1) classically appear during or after febrile illness — hence the name "fever blister." Genital HSV can similarly be triggered by systemic illness.
• Local skin trauma: For genital herpes, intense friction during sexual activity or prolonged pressure to the area can trigger reactivation. Using lubrication during sex and wearing comfortable underwear may reduce this trigger.
• Sun exposure: For orolabial HSV, UV light exposure is a well-established trigger. SPF-containing lip balm significantly reduces sun-triggered cold sores.
• Menstruation and hormonal changes: Many women notice increased outbreak frequency around menstruation. Hormonal contraception sometimes reduces this pattern.
• Immune suppression: Any condition that reduces immune function (HIV, cancer chemotherapy, organ transplant medications) can increase outbreak frequency.

While triggers cannot always be eliminated, identifying your personal pattern helps with management. If you consistently have outbreaks after a particular trigger, suppressive therapy may be especially valuable.

Swabbing an active herpetic lesion for viral culture or PCR is the most definitive way to confirm a herpes diagnosis. PCR is significantly more sensitive than culture (especially for healing or partially crusted lesions), and most modern labs use PCR as the primary confirmatory test. Key points:

• Swabbing must be done early — ideally within 48 hours of the lesion appearing, before crusting, when viral load is highest
• A negative swab does not rule out herpes — if the lesion is healing or the viral load is low, sensitivity drops significantly
• PCR can distinguish HSV-1 from HSV-2, which has implications for counseling about transmission risk and recurrence likelihood
• VZV PCR from vesicle fluid diagnoses shingles definitively and is preferred over clinical diagnosis for atypical presentations

Type-specific IgG blood tests (glycoprotein G-based immunoassays) detect antibodies to HSV-1 or HSV-2, indicating prior infection. The two FDA-cleared tests with the best performance are the HerpeSelect HSV-1 IgG and HSV-2 IgG assays (Focus Diagnostics) and Kalon HSV-2 IgG assay (widely used internationally). Key interpretation points:

• Time to seroconversion: IgG antibodies to HSV develop over 12 weeks after primary infection. A negative IgG result in the first 2–3 months after a suspected exposure does not rule out recent infection. Retesting at 3 months is recommended if initial infection is suspected.
• False positives at low index values: HerpeSelect HSV-2 IgG results in the 1.1–3.5 index range (low positive) have a significant false positive rate (up to 50% in some studies, particularly in low-prevalence populations). A result in this range should be confirmed with a different assay (Kalon or Biokit) or with clinical context before a herpes diagnosis is delivered to the patient.
• IgM testing: IgM herpes tests are not type-specific and have poor sensitivity and specificity for acute infection. They should not be used to diagnose acute herpes and they are not recommended in clinical guidelines. Do not use IgM results to diagnose primary herpes.
• Asymptomatic infection: Type-specific IgG can detect herpes in people who have never had a recognized outbreak — approximately two-thirds of people with HSV-2 do not know they are infected. This is the basis of the debate about universal screening, which current CDC guidelines do not recommend in the absence of symptoms (because the harms of labeling and anxiety in unaware individuals may outweigh benefits in the general population — though screening may be beneficial in specific high-risk contexts).

A positive herpes diagnosis often carries more psychological weight than the disease itself warrants. Context matters enormously:

• HSV-1 genital herpes (increasingly common, often acquired through oral sex) has a significantly lower recurrence rate than HSV-2 genital herpes — most HSV-1 genital infections recur fewer than 2 times per year and some people never have a second outbreak
• HSV-2 recurrence rates vary widely: some people have 10+ recurrences per year; others have 1–2 and then go years without one. The first year after primary infection tends to have the highest recurrence frequency, which often decreases over time
• A positive HSV-2 IgG does not tell you when or how you were infected — it could be a recent infection or one from 20 years ago. The test cannot date infection
• Testing positive for HSV does not mean you were necessarily exposed recently or through infidelity — many people carry herpes unknowingly for years before a first recognized outbreak

• More frequent outbreaks: In people with HIV (especially with CD4 counts below 200), HSV recurrences may occur weekly rather than once or twice a year. The immune system’s inability to suppress viral reactivation allows more frequent and prolonged shedding.
• More severe and extensive lesions: Ulcers that would be small and self-limited in an immunocompetent person can become large, deep, necrotic, and slow-healing in immunocompromised patients. Perianal HSV ulcers — particularly in HIV-positive men who have sex with men — can extend and be mistaken for other conditions including Crohn’s disease, anal cancer, or other sexually transmitted infections.
• Atypical locations: Esophageal herpes (causing dysphagia and odynophagia), tracheal herpes, and herpes of the anorectal mucosa occur more commonly in immunocompromised patients. Disseminated HSV involving liver (fulminant hepatitis), lungs, or the central nervous system can occur and is life-threatening.
• Herpes encephalitis: HSV encephalitis occurs in both immunocompetent and immunocompromised patients but may be more aggressive and recur more frequently in the latter. In transplant recipients and patients with lymphoma, VZV encephalitis is a recognized complication.
• Varicella (primary chickenpox) in adult transplant recipients: Reactivation-naive adult transplant recipients who encounter varicella are at risk of severe disseminated disease. Varicella vaccination before transplantation (when still in a non-immunosuppressed state) is strongly recommended. Post-exposure prophylaxis with varicella-zoster immune globulin (VZIG) is indicated for susceptible immunocompromised patients exposed to chickenpox.

• Prophylactic antiviral therapy: Many immunocompromised patients (solid organ transplant recipients, hematopoietic stem cell transplant recipients, patients with advanced HIV, those on high-dose chemotherapy for leukemia/lymphoma) receive prophylactic antiviral therapy with acyclovir or valacyclovir to prevent HSV and VZV reactivation during the period of deepest immunosuppression. This has dramatically reduced the incidence of serious HSV/VZV complications in transplant medicine.
• Higher antiviral doses for treatment: Active HSV disease in immunocompromised patients typically requires higher antiviral doses and longer treatment duration than in immunocompetent patients. IV acyclovir may be needed for moderate-to-severe disease. Recurrence while on prophylaxis should prompt evaluation for antiviral resistance.
• Antiviral resistance: Prolonged exposure to acyclovir in immunocompromised patients can select for thymidine kinase-deficient HSV mutants that are resistant to all acyclovir-class drugs (including valacyclovir and famciclovir). Foscarnet (IV) is the primary alternative for acyclovir-resistant HSV; cidofovir is a second-line agent. Resistance testing (HSV genotyping for thymidine kinase mutations) is available at reference virology laboratories and should be requested when a patient fails to respond to adequate antiviral doses.
• Shingles vaccine timing: The live Zostavax vaccine is contraindicated in severely immunocompromised patients. Shingrix (recombinant, adjuvanted, non-live) is safe in immunocompromised patients and is recommended for immunocompromised adults 18+ (including HIV-positive individuals with CD4 ≥200, transplant recipients off intense immunosuppression, patients on TNF inhibitors). For HIV-positive patients, Shingrix is now recommended starting at age 50+ (or earlier for those with HIV-related immunosuppression history).

• Frequent recurrences: Six or more outbreaks per year is the traditional threshold for initiating suppressive therapy, though many providers offer it for fewer recurrences if they are significantly affecting quality of life. Daily therapy reduces outbreak frequency by approximately 70–80% and reduces outbreak severity and duration.
• Serodiscordant couples: The landmark VALOR trial demonstrated that valacyclovir 500 mg once daily reduced transmission of HSV-2 from an infected to an uninfected partner by 48% (when combined with condom use and partner education). This is a meaningful reduction, though not elimination of risk. Suppression in this context is standard of care when transmission prevention is a goal.
• Psychological benefit: Many people with herpes find that knowing they are doing something proactive reduces anxiety about transmission and about future outbreaks. This psychological benefit is a legitimate reason to start suppression even if outbreak frequency alone would not meet the traditional threshold.
• Immunocompromised patients: People with HIV, organ transplant recipients, or those on immunosuppressive therapies often have more frequent, more severe, and sometimes atypical herpes recurrences. Long-term suppression is essentially universal in these populations.

Three antivirals are used for suppressive therapy:

• Valacyclovir (Valtrex): 500 mg once daily (or 1 g once daily for patients with frequent recurrences despite 500 mg). Most convenient dosing. Generic available and affordable.
• Acyclovir: 400 mg twice daily. Slightly less convenient than once-daily valacyclovir but equally effective and often less expensive. Long-term safety record spanning 40+ years. The 1 mg/day dose used in the CASG 204 suppression trial over 6 years showed no significant safety concerns.
• Famciclovir (Famvir): 250 mg twice daily. Less commonly used for suppression but an option for patients who do not tolerate the others.

Long-term suppressive therapy is well tolerated. The most commonly reported side effects are headache and nausea, which are usually mild and often resolve with time. Renal function monitoring is recommended in patients with pre-existing kidney disease, but routine monitoring is not necessary in people with normal kidney function on standard doses. There is no evidence of significant adverse effects from years of continuous daily antiviral use in immunocompetent adults. Many people continue suppressive therapy for 10+ years without issues. Duration of therapy is a personal decision — some people take it indefinitely; others take it for several years and then reassess whether outbreaks have naturally become less frequent.

HSV keratitis occurs when HSV (usually HSV-1) infects the cornea. It is the leading infectious cause of corneal blindness in developed countries, affecting approximately 1.5 million people per year worldwide. Primary ocular HSV typically presents as a conjunctivitis or lid skin vesicles, often in children. Recurrent HSV keratitis affects the corneal stroma (the deep layers of the cornea) and causes progressive scarring and vision loss over time.

Warning signs that require same-day ophthalmology evaluation:

• Eye pain, redness, and photophobia (light sensitivity) — especially with a known history of cold sores or prior eye herpes
• Blurred or decreased vision in one eye
• Dendritic (branching) lesions on the cornea visible on slit-lamp exam (this is pathognomonic for HSV keratitis)
• Foreign body sensation that does not resolve

Treatment: Topical antivirals (trifluridine drops, ganciclovir gel) for epithelial disease. Oral antivirals (acyclovir or valacyclovir) for stromal disease. Topical corticosteroids may be used for stromal/immune keratitis under close ophthalmology supervision. Long-term oral suppressive therapy (acyclovir 400 mg twice daily) significantly reduces recurrence rates — the HEDS (Herpetic Eye Disease Study) demonstrated a 41% reduction in recurrent stromal keratitis with long-term acyclovir suppression. Never use topical steroid eye drops without ophthalmology involvement if HSV is suspected — steroids can dramatically worsen epithelial HSV keratitis.

Herpes Zoster Ophthalmicus occurs when VZV reactivates in the ophthalmic branch (V1) of the trigeminal nerve. It accounts for approximately 10–15% of all shingles cases. HZO can cause conjunctivitis, keratitis, uveitis (inflammation inside the eye), retinal necrosis, optic neuritis, and post-herpetic neuralgia affecting the face and scalp. A critical warning sign is the Hutchinson’s sign: vesicles on the tip or side of the nose, indicating nasociliary nerve involvement and predicting high risk of intra-ocular complications. Any shingles rash involving the face around the eye warrants same-day ophthalmological evaluation, not next-week outpatient follow-up. Treatment is oral antiviral therapy (valacyclovir 1 g three times daily for 7–10 days) initiated as early as possible, with topical steroids and other ophthalmological interventions as needed for specific complications. Prevention of HZO is one of the primary motivations for shingles vaccination in adults aged 50+ (Shingrix).

If you have had genital herpes for years before becoming pregnant, the risk to your newborn is very low — approximately 1–4 per 10,000 births. Your body has built up significant antibody levels that cross the placenta and provide the newborn with substantial protection. The key intervention is antiviral suppressive therapy from 36 weeks gestation (acyclovir 400 mg three times daily, or valacyclovir 500 mg twice daily) to suppress viral shedding, reduce the likelihood of active lesions at the time of delivery, and lower — but not completely eliminate — the risk of viral transmission during birth.

Even with suppressive therapy, if you have active genital lesions or prodromal symptoms (tingling, burning) at the onset of labor, cesarean delivery is recommended to minimize neonatal exposure. The decision to proceed with vaginal delivery in the absence of visible lesions while on suppressive therapy is acceptable and is the standard approach.

A first-episode genital herpes infection acquired during the third trimester is the most dangerous scenario for the baby. This is because the mother has not yet developed protective antibodies, viral shedding is high and prolonged, and the antibody-negative mother cannot transfer protective IgG to the newborn before birth. Neonatal herpes transmission risk in this scenario is estimated at 40–50%. First-episode infection in the first or second trimester is less dangerous for the newborn (because there is time for antibody development) but still requires careful management including antiviral therapy throughout the remaining pregnancy.

Key protective measures for primary infection in pregnancy:

• Immediate antiviral treatment (acyclovir 400 mg three times daily or valacyclovir 1 g twice daily) for the primary episode
• Continuation of suppressive therapy from 36 weeks
• Cesarean delivery is strongly recommended if primary infection was acquired in the third trimester, regardless of whether lesions are visible at delivery, because of the high shedding rate and lack of protective maternal antibody
• Neonatal herpes surveillance in the newborn for 4–6 weeks after birth with neonatology follow-up

Neonatal herpes is a rare but serious condition that affects approximately 1,500–2,200 newborns per year in the United States. It presents in three forms: skin/eye/mouth (SEM) disease (least severe, though still requiring IV antiviral treatment), central nervous system disease (encephalitis, seizures, altered consciousness), and disseminated disease (multi-organ involvement including liver, lung, brain). Disseminated disease and CNS disease carry significant mortality and morbidity even with treatment — hence the importance of prevention.

Signs that should prompt urgent evaluation of a newborn (especially from a mother with herpes):

• Clusters of blisters or vesicles on skin, scalp, or in the mouth (may not appear in disseminated or CNS disease)
• Fever, irritability, poor feeding, or lethargy in the first 4 weeks of life
• Seizures at any age in the neonatal period
• Jaundice or liver enlargement in the first 2 weeks (disseminated disease)

If neonatal herpes is suspected, immediate evaluation at a tertiary care center with neonatal intensive care capabilities is essential. IV acyclovir treatment must be started empirically before diagnostic confirmation. Delays in treatment significantly worsen outcomes in CNS and disseminated disease. Parents who know they have herpes should explicitly communicate this to their pediatric providers at the newborn’s first visits.

• Generic antivirals: Acyclovir, valacyclovir, and famciclovir are all available as generics. Valacyclovir 500 mg (for suppressive therapy) typically costs $10–30/month at most pharmacies. GoodRx and similar discount programs can further reduce costs.
• Shingrix cost: Approximately $150–200 per dose without insurance. Covered by most private insurance, Medicare Part D (no cost-sharing under the Inflation Reduction Act), and the VA for veterans.
• Patient assistance programs:
  • GSK Vaccines Access Program (for Shingrix): 1-888-825-5249
  • NeedyMeds (needymeds.org, 800-503-6897): database of prescription assistance programs
  • RxAssist (rxassist.org): comprehensive database of patient assistance programs
• STI clinics: Many public health departments and Planned Parenthood locations offer low-cost or free STI testing and treatment, including herpes diagnosis and antiviral prescriptions.

• American Sexual Health Association (ASHA) — ashasexualhealth.org — runs the Herpes Resource Center. Reliable information, support forums, and educational materials.
• CDC STI Information Line — 800-232-4636 (800-CDC-INFO)
• Planned Parenthood — plannedparenthood.org — provides testing, treatment, and counseling at locations nationwide
• National Herpes Hotline (ASHA) — 919-361-8488
• Crisis support: If you are experiencing a mental health crisis related to your diagnosis, contact the 988 Suicide & Crisis Lifeline (call or text 988) or the Crisis Text Line (text HOME to 741741)

• Medicaid: Covers antiviral medications and Shingrix in most states. Utah Medicaid: medicaid.utah.gov, 1-866-435-7414
• Medicare Part D: Covers Shingrix with no cost-sharing (Inflation Reduction Act). 800-633-4227
• VA Healthcare: Veterans can receive herpes testing, treatment, and Shingrix vaccination through VA facilities. 800-827-1000
• Title X Family Planning Clinics: Federally funded clinics that provide low-cost STI services based on ability to pay. Find locations at hhs.gov/opa

• Antivirals: Acyclovir, valacyclovir, and famciclovir are all FDA-approved for HSV and VZV. All available as generics.
• Shingrix: FDA-approved 2017. ACIP-recommended for adults 50+ and immunocompromised adults 19+.
• Zostavax: Discontinued in the US (November 2020). Replaced by Shingrix.
• Pritelivir: Not yet FDA-approved; available through clinical trials and expanded access programs.

• Antivirals: Acyclovir, valacyclovir, and famciclovir are widely available across EU member states.
• Shingrix: EMA-approved. Recommended by most national immunization programs for adults 50+, with some variation in age thresholds and reimbursement across countries.
• Amenamevir: Not approved in the EU.

• Amenamevir (Amenalief): Approved in Japan (2017) for shingles. The first helicase-primase inhibitor to reach the market anywhere in the world.
• Antivirals: Acyclovir, valacyclovir, and famciclovir available.
• Shingrix: Approved in Japan.

• Canada: Acyclovir, valacyclovir, and famciclovir available. Shingrix approved and recommended by NACI for adults 50+. Provincial coverage for Shingrix varies — check with provincial health authority.
• United Kingdom: Antivirals available through the NHS. GUM (genitourinary medicine) clinics provide free, confidential testing and treatment for genital herpes. Shingrix is available through the NHS shingles vaccination program for eligible age groups (program is being expanded).

Access to herpes treatment varies significantly worldwide:

• Acyclovir is on the WHO List of Essential Medicines and is available in most countries, though supply and affordability remain challenges in some settings.
• Valacyclovir is less widely available in low-income countries due to higher cost, though generic production is expanding.
• Shingrix availability is limited in many low- and middle-income countries due to cost and supply constraints.
• WHO has identified HSV vaccine development as a priority and published preferred product characteristics to guide research and development.
• In sub-Saharan Africa, where HSV-2 prevalence is highest (often 30–50% of adults) and the interaction with HIV is most consequential, access to suppressive therapy remains limited.

• Simplirix / Herpevac (GSK gD2 subunit prophylactic vaccine) FAILED
  The largest prophylactic HSV vaccine trial (Herpevac Trial for Women, over 8,000 participants) showed that the glycoprotein D subunit vaccine did not prevent HSV-2 infection, despite promising phase 2 results. Partial efficacy against HSV-1 genital infection was observed but insufficient for clinical use. Development was discontinued.
• GEN-003 therapeutic vaccine (Genocea) DISCONTINUED
  A protein subunit therapeutic vaccine that showed modest reduction in viral shedding in a phase 2 trial but was discontinued when Genocea shifted its pipeline to cancer immunotherapy. The approach did not produce sufficiently robust results for further development.
• Zostavax (live attenuated zoster vaccine, Merck) DE-ADOPTED
  Zostavax was FDA-approved in 2006 and was the first shingles vaccine. It was approximately 51% effective at preventing shingles and 67% effective against PHN, but efficacy waned significantly after 5 years and it could not be given to immunocompromised patients (being a live vaccine). It was superseded by Shingrix and discontinued in the US in November 2020.
• Topical acyclovir cream for genital herpes DE-ADOPTED
  While topical acyclovir/penciclovir have modest benefit for oral cold sores, topical antiviral therapy for genital herpes has been shown to be ineffective compared to oral therapy. The CDC does not recommend topical antiviral treatment for genital herpes. Oral therapy is always preferred.
• Nonoxynol-9 for HSV prevention HARMFUL
  Nonoxynol-9, a spermicide once promoted as a potential microbicide against STIs, was found to actually increase the risk of HSV and HIV transmission by causing mucosal irritation and disruption. It should not be used for STI prevention.
• Suppressive acyclovir to prevent HIV acquisition (in HSV-2-positive individuals) FAILED
  Large trials (HPTN 039 and Partners in Prevention) tested whether daily acyclovir in HSV-2-positive individuals would reduce HIV acquisition. Despite reducing HSV-2 genital ulceration, acyclovir did not reduce HIV transmission risk. HIV pre-exposure prophylaxis (PrEP) with antiretroviral drugs remains the effective approach.

• Acyclovir — the first antiviral drug effective against herpes, FDA-approved in 1982. Available as oral, IV, and topical formulations. The foundation of herpes treatment.
• Antibody — a protein produced by the immune system in response to infection. Type-specific antibodies (IgG to gG-1 or gG-2) are used to diagnose past HSV infection via blood tests.
• Asymptomatic shedding — the presence of herpes virus on skin or mucosal surfaces without visible symptoms. The most common mode of HSV transmission to new partners.
• Dermatome — the area of skin supplied by a single spinal nerve. Shingles follows a dermatomal distribution, appearing on one side of the body.
• Disseminated — spread widely through the body. Disseminated herpes can affect multiple dermatomes or internal organs, primarily in immunocompromised patients.
• Episodic therapy — antiviral treatment taken only during outbreaks, as opposed to daily suppressive therapy.
• Famciclovir — an oral antiviral prodrug of penciclovir, used for HSV and VZV treatment.
• Ganglion (plural: ganglia) — a cluster of nerve cell bodies. Herpes viruses establish latency in sensory ganglia (trigeminal for oral HSV, sacral for genital HSV, dorsal root for VZV).
• Helicase-primase inhibitor — a new class of antiviral drug (e.g., pritelivir, amenamevir) that works by a different mechanism than acyclovir-class drugs. May be effective against acyclovir-resistant strains.
• HSV-1 — herpes simplex virus type 1. Most commonly causes oral herpes (cold sores) but increasingly causes genital herpes as well.
• HSV-2 — herpes simplex virus type 2. The primary cause of genital herpes. More likely to recur frequently than genital HSV-1.
• Hutchinson sign — vesicles on the tip or side of the nose during shingles, indicating nasociliary nerve involvement and predicting a high risk of eye complications.

• IgG — immunoglobulin G, the antibody class used in type-specific serologic testing for HSV. Develops 2–12 weeks after infection.
• IgM — immunoglobulin M, an early antibody that is unreliable for HSV diagnosis and should not be used.
• Immunocompromised — having a weakened immune system due to disease (HIV, cancer) or treatment (chemotherapy, transplant medications, corticosteroids).
• Keratitis — inflammation of the cornea. HSV keratitis is the leading infectious cause of corneal blindness in developed countries.
• Latency — the state in which herpes virus remains dormant in nerve cells, not actively replicating. Antiviral drugs cannot eliminate latent virus.
• Neonatal herpes — herpes infection in a newborn, usually acquired during delivery. Rare but serious, requiring IV acyclovir treatment.
• PCR (polymerase chain reaction) — the gold standard laboratory test for detecting herpes virus in a lesion swab. Highly sensitive and specific, and can distinguish HSV-1 from HSV-2.
• PHN (postherpetic neuralgia) — persistent pain lasting more than 90 days after a shingles rash, caused by nerve damage. The most common and debilitating complication of shingles.
• Prodrome — early warning symptoms (tingling, itching, burning) that precede a visible herpes outbreak by hours to days. Starting antiviral treatment during the prodrome improves effectiveness.

• Reactivation — the process by which latent herpes virus becomes active again, traveling from the ganglia to the skin to cause symptoms or asymptomatic shedding.
• Recurrence — a repeat outbreak of herpes symptoms after the primary episode. Frequency varies widely among individuals and tends to decrease over time.
• Serodiscordant — a couple in which one partner has antibodies to a herpes virus (is infected) and the other does not.
• Serology — blood testing for antibodies, used to detect past herpes infection when no active lesion is present.
• Shingles (herpes zoster) — a painful, blistering rash caused by reactivation of varicella-zoster virus (VZV) from dorsal root ganglia. Appears in a dermatomal distribution on one side of the body.
• Shingrix — a recombinant, adjuvanted vaccine against shingles (herpes zoster). Over 90% effective. Recommended for adults 50+ and immunocompromised adults 19+.
• Suppressive therapy — daily antiviral medication taken to reduce outbreak frequency, asymptomatic shedding, and transmission risk.
• Tzanck smear — an older diagnostic technique involving scraping a lesion and examining it under a microscope. Cannot distinguish HSV types or HSV from VZV. Largely superseded by PCR.
• Valacyclovir — the oral prodrug of acyclovir with higher bioavailability and more convenient dosing. The most commonly prescribed antiviral for herpes.
• VZV (varicella-zoster virus) — the herpes virus that causes chickenpox (primary infection) and shingles (reactivation). Also called human herpesvirus 3 (HHV-3).
• Western blot — the gold standard confirmatory serologic test for HSV, performed at the University of Washington. Used when standard IgG serology results are equivocal.

Guidelines:

• CDC Sexually Transmitted Infections Treatment Guidelines (2021, updated 2024) — Herpes Simplex section
• WHO Global Health Sector Strategies on HIV, Viral Hepatitis, and STIs (2022–2030)
• ACIP Recommendations for Recombinant Zoster Vaccine (Shingrix) — MMWR 2018 and 2021 updates
• AAD (American Academy of Dermatology) Guidelines for Herpes Simplex
• ACOG Practice Bulletin: Management of Genital Herpes in Pregnancy
• BASHH (British Association for Sexual Health and HIV) Herpes Management Guidelines

Landmark studies and key references:

• CDC STI Information (cdc.gov/sti) — Comprehensive herpes information and treatment guidelines. 800-232-4636
• American Sexual Health Association (ASHA) (ashasexualhealth.org) — Herpes Resource Center, support forums, educational materials
• WHO Herpes Simplex Virus Fact Sheet (who.int) — Global epidemiology and strategy
• ClinicalTrials.gov (clinicaltrials.gov) — Official U.S. registry of clinical trials
• PubMed (pubmed.ncbi.nlm.nih.gov) — Free public database of medical research
• Planned Parenthood (plannedparenthood.org) — Testing, treatment, and educational resources nationwide