Genital herpes is a sexually transmitted infection caused by human herpesvirus 1 or 2. It causes ulcerative genital lesions. Diagnosis is clinical with laboratory confirmation by culture, polymerase chain reaction, or serologic testing. Treatment is with antiviral medications.
Genital herpes is a common sexually transmitted infection caused by human herpesviruses 1 (HSV-1) or 2 (HSV-2). Genital herpes caused by HSV-2 affected > 400 million of people ages 15 to 49 years worldwide in 2016; prevalence of HSV-2 is twice as high in women compared with men. Most cases of genital herpes are caused by HSV-2, but the proportion of cases due to HSV-1 has been increasing. (See World Health Organization: Herpes Simplex Virus.)
After the initial infection, HSV remains dormant in nerve ganglia, from which it can periodically reactivate. When the virus reactivates, it may or may not cause symptoms (ie, genital lesions). Transmission may occur through contact with the lesions or, more often, via skin-to-skin contact with sex partners when lesions are not apparent (called asymptomatic shedding).
Pregnant women with genital herpes can transmit HSV (usually HSV-2) to the fetus or neonate. Typically, HSV is transmitted during delivery via contact with vaginal secretions containing HSV. The virus is rarely transmitted transplacentally. Mothers with primary (newly acquired) HSV genital infection have a higher risk of transmitting HSV to the neonate. Most women who transmit HSV to neonates do not have symptoms of HSV infection at the time of delivery. Neonatal HSV infection is a serious, potentially fatal infection.
Symptoms and Signs of Genital Herpes
Most cases of primary genital herpes do not cause noticeable symptoms; many people infected with HSV-1 or HSV-2 do not know that they have genital herpes.
Primary genital lesions develop 4 to 7 days after contact. The vesicles usually erode to form ulcers that may coalesce. Lesions may occur in the following locations:
On the prepuce, glans penis, and penile shaft in men
On the labia, clitoris, perineum, vagina, and cervix in women
Around the anus and in the rectum in men or women who engage in receptive rectal intercourse
This photo shows pustules in primary genital herpes of the vulva.
© Springer Science+Business Media
This photo shows ulcerations in the vulva that are caused by genital herpes.
© Springer Science+Business Media
This photo shows vesicles and ulcers in the vulva of a woman with recurrent genital herpes.
© Springer Science+Business Media
This photo shows a cluster of vesicles on the penile shaft in a man with genital herpes.
© Springer Science+Business Media
This photo shows groups and clusters of vesicles and ulcers in a man with primary genital herpes.
© Springer Science+Business Media
This photo shows widespread ulceration of the penis and scrotum due to coalescence of smaller lesions in a man with severe genital herpes infection.
© Springer Science+Business Media
This photo shows pustules in primary genital herpes of the vulva.
© Springer Science+Business Media
This photo shows ulcerations in the vulva that are caused by genital herpes.
© Springer Science+Business Media
This photo shows vesicles and ulcers in the vulva of a woman with recurrent genital herpes.
© Springer Science+Business Media
This photo shows a cluster of vesicles on the penile shaft in a man with genital herpes.
© Springer Science+Business Media
This photo shows groups and clusters of vesicles and ulcers in a man with primary genital herpes.
© Springer Science+Business Media
This photo shows widespread ulceration of the penis and scrotum due to coalescence of smaller lesions in a man with severe genital herpes infection.
© Springer Science+Business Media
Urinary hesitancy, dysuria, urinary retention, constipation, or severe sacral neuralgia may occur.
Scarring may follow healing. The lesions recur in 80% of patients with HSV-2 and in 50% of those with HSV-1.
Primary genital lesions are usually more painful, prolonged, and widespread, involve regional adenopathy, and are more likely to be accompanied by constitutional symptoms than recurrent genital lesions. Recurrent lesions tend to be milder and cause fewer symptoms.
Diagnosis of Genital Herpes
History and physical examination
Culture and polymerase chain reaction (PCR)
Serologic testing
Diagnosis of genital herpes is often clinical based on characteristic lesions; clusters of vesicles or ulcers on an erythematous base are unusual in genital ulcers other than those due to HSV. However, these lesions are absent in many patients.
Tests for HSV should be done to confirm the diagnosis if it is not clear.
Testing is usually done using a sample of fluid from the base of a vesicle or of a newly ulcerated lesion, if present. Absence of HSV in culture, especially in patients without active lesions, does not rule out HSV infection because viral shedding is intermittent. Also, culture has limited sensitivity; PCR is more sensitive and is favored over culture.
Serologic tests can accurately detect HSV-1 and HSV-2 antibodies, which develop during the first several weeks after infection and then persist. Thus, if genital herpes is thought to be recently acquired, tests may have to be repeated to allow time for seroconversion.
HSV serologic testing should be considered for the following;
To evaluate patients who have no suspicious genital lesions but who require or request evaluation (eg, because of past genital lesions or high-risk behaviors)
To help determine risk of developing lesions
To identify pregnant women who do not have genital lesions but are at risk of transmitting herpes to the neonate during delivery
To determine whether a person is susceptible to infection from a sex partner with genital herpes
Treatment of Genital Herpes
Genital herpes is treated with antivirals.
Doses should be adjusted for renal insufficiency. Adverse effects are infrequent with oral administration but may include nausea, vomiting, diarrhea, headache, and rash.
Topical antivirals have only little value, and their use is discouraged.
Evaluation of sex partners of patients with genital herpes is important.
Prevention of Genital Herpes
The best ways to avoid genital herpes are
Abstaining from sexual contact (vaginal, anal, and oral sex)
Being in a long-term mutually monogamous relationship with a partner who has been tested and is not infected
Risk of genital herpes can by reduced by
Using latex condoms correctly and consistently
However, condoms do not cover all areas that can be affected and thus do not fully protect against genital herpes.
Patients with genital herpes should abstain from sexual activity when they have lesions or other herpes symptoms. Patients should be reminded that they can transmit the infection even when they do not have any symptoms.
Preventing neonatal HSV infection
Efforts to prevent neonatal transmission of HSV have not been very effective. Universal screening has not been recommended or shown to be effective.
Pregnant women should be asked about a history of genital herpes at a first prenatal visit and should be counseled about the importance of not contracting herpes during pregnancy.
Fetal scalp monitors should be avoided during labor on infants whose mothers have a history of genital herpes.
Key Points
After the initial infection, HSV remains dormant in nerve ganglia, from which it can periodically reactivate.
Transmission may occur through contact with the lesions, but viral shedding and transmission can also occur when lesions are not apparent (asymptomatic shedding).
Most initial infections do not cause symptoms, but primary genital lesions are usually more painful, prolonged, and widespread than recurrent genital lesions.
Diagnose based on characteristic genital lesions in patients with lesions and confirm by culture, PCR (preferred), and/or serologic tests for HSV.
More Information
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