Genital Herpes Simplex

INTRODUCTION

Herpes simplex virus (HSV) is the most prevalent cause of genital ulcer disease among sexually active people.
It is a chronic, lifelong viral infection and so presents with recurrent episodes.
HSV2 is almost always sexually transmitted.
HSV1 is usually acquired during childhood through nonsexual contacts.
Infections can be asymptomatic or unrecognized, but the patient can still shed the virus and transmit the disease.

EPIDEMIOLOGY

About 50 million people have genital herpes in the United States.
HSV2 is more common to cause genital infections (30% HSV1, 70% HSV2), although the incidence of HSV1 genital infection is probably increasing.
HSV2 is more likely to cause recurrent episodes.
Prior HSV1 infection can alleviate symptoms of subsequent HSV2 infection, and it can increase the chances of asymptomatic HSV2 infection by threefold.
Transmission occurs most commonly from asymptomatic patients or from those with unrecognized infection.
Risk of transmission increases with male source and with negative HSV antibodies.
Male latex condoms might reduce the risk for genital herpes transmission.
It increases risk of HIV acquisition and transmission.
HSV perinatal transmission can be associated with fetal mortality and morbidity.

CLINICAL MANIFESTATIONS

Primary Infection

Can be asymptomatic, subclinical, mild, or severe.
Incubation period is normally from 2 to 12 days.
Painful vesicular lesions/painful ulcers, and tender lymphadenopathy occur.
Lesions are usually multiple.
Fever, dysuria, and mucoid discharge can occur especially in females.
Can cause urethritis and cervicitis, which cannot be distinguished clinically from chlamydia and gonorrhea.
Usually more severe infections occur in female.

Recurrent Infection

Usually less severe and with fewer lesions than primary infection.
Has shorter duration of symptom and shorter duration of shedding.
Lesions may be preceded by a prodrome of tingling or pain.
Risk of frequent recurrences is higher with more severe and longer initial episode, in immunosuppressed, and with HSV2 compared to HSV1.
More common in males than females.
Median recurrence rates are four to five episodes per year, then a gradual decrease in rate over the years.

Proctitis

Especially in MSM (men who have sex with men).
Causes rectal pain, discharge, and tenesmus.
A perianal lesion may be present.

DIAGNOSIS

1. Culture

Is the gold standard.
Highest yield with vesicular lesions.
Has low sensitivity (about 50%).
Typing should be done to detect the type of HSV when positive if possible.

2. PCR

Is more sensitive and is superior to virus isolation and culture.
Is not FDA approved.
Allows differentiation between HSV1 and HSV2.
Can detect asymptomatic shedding of the virus.

3. Type-specific serology

These are based upon glycoprotein G (G2 for HSV2 and G1 for HSV1)
Appear within the first week of infection and remain for life.

4. Cytological changes: nonspecific.

MANAGEMENT

Antiviral therapy controls signs and symptoms but does not eradicate the virus. It does not affect risk or frequency of recurrence after medication is stopped.

Treatment Regimens: See Table 12.1

Treatment can be extended if healing is incomplete in 10 days.

Suppressive therapy for recurrent infections: see Table 12.1.

Decreases recurrence by 70% to 80%, and decreases transmission to partners
Improves quality of life, and is preferred over episodic therapy.
Does not reduce the increased risk for HIV acquisition associated with HSV infection.

Table 12-1 Treatment of HSV in non-HIV patients

Regimens for First Episode: (Any of the Following)	Regimens for Suppressive Therapy (Any of the Following)	Regimens for Episodic Therapy (Any of the Following)
Acyclovir 400 mg orally three times a day for 7-10 days Acyclovir 200 mg orally five times a day for 7-10 days Famciclovir 250 mg orally three times a day for 7-10 days Valacyclovir 1 g orally twice a day for 7-10 days	Acyclovir 400 mg orally twice a day Famcyclovir 250 mg orally twice a day Valacyclovir 500 mg orally once a day Valacyclovir 1 g orally once a day	Acyclovir 400 mg orally three times a day for 5 days Acyclovir 800 mg orally twice a day for 5 days Acyclovir 800 mg orally three times a day for 2 days Famciclovir 125 mg orally twice daily for 5 days Famciclovir 1,000 mg orally twice daily for 1 day Famciclovir 500 mg once, followed by 250 mg twice daily for 2 days Valacyclovir 500 mg orally twice a day for 3 days Valacyclovir 1 g orally once a day for 5 days