Herpes Simplex Virus (HSV) Infections

Lesions may appear anywhere on the skin or mucosa but are most frequent in the following locations:

Generally, after a prodromal period (typically < 6 hours in recurrent HSV-1) of tingling discomfort or itching, clusters of small, tense vesicles appear on an erythematous base. Clusters vary in size from 0.5 to 1.5 cm but may coalesce. Lesions on the nose, ears, eyes, fingers, or genitals may be particularly painful.

Vesicles typically persist for a few days, then rupture and dry, forming a thin, yellowish crust.

Healing generally occurs within 10 to 19 days after onset in primary infection or within 5 to 10 days in recurrent infection. Lesions usually heal completely, but recurrent lesions at the same site may cause atrophy and scarring. Skin lesions can develop secondary bacterial infection. In patients with depressed cell-mediated immunity due to HIV infection or other conditions, prolonged or progressive lesions may persist for weeks or longer. Localized infections can disseminate, particularly—and often dramatically—in immunocompromised patients.

Acute herpetic gingivostomatitis usually results from primary infection with HSV-1, typically in children. Herpetic pharyngitis can occur in adults as well as children. Occasionally, through oral-genital contact, the cause is HSV-2. Intraoral and gingival vesicles rupture, usually within several hours to 1 or 2 days, to form ulcers. Fever and pain often occur. Difficulty eating and drinking may lead to dehydration. After resolution, the virus resides dormant in the semilunar ganglion.

Herpes labialis is usually a recurrence of HSV. It develops as ulcers (cold sores) on the vermilion border of the lip or, much less commonly, as ulcerations of the mucosa of the hard palate.

Genital herpes Genital Herpes 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... read more is the most common ulcerative sexually transmitted infection in developed countries. Genital HSV can be caused by HSV-1 or HSV-2.

Herpes simplex keratitis Herpes Simplex Keratitis Herpes simplex keratitis is corneal infection with herpes simplex virus. It may involve the iris. Symptoms and signs include foreign body sensation, lacrimation, photophobia, and conjunctival... read more (HSV infection of the corneal epithelium) causes pain, tearing, photophobia, and corneal ulcers that often have a branching pattern.

Herpetic whitlow Herpetic Whitlow Herpetic whitlow is a cutaneous infection of the distal aspect of the finger caused by herpes simplex virus. (See also Overview and Evaluation of Hand Disorders.) Herpetic whitlow may cause... read more , a swollen, painful, erythematous lesion of the finger, results from inoculation of HSV through the skin and is most common among health care practitioners.

Neonatal HSV infection Neonatal Herpes Simplex Virus (HSV) Infection Neonatal herpes simplex virus infection is usually transmitted during delivery. A typical sign is vesicular eruption, which may be accompanied by or progress to disseminated disease. Diagnosis... read more develops in neonates, including those whose mothers have no suggestion of current or past herpes infection. It is most commonly transmitted during birth through contact with vaginal secretions containing HSV and usually involves HSV-2.

Neonatal HSV infection usually develops between the 1st and 4th week of life, often causing mucocutaneous vesicles or central nervous system involvement. It causes major morbidity and mortality.

Herpes encephalitis Encephalitis Encephalitis is inflammation of the parenchyma of the brain, resulting from direct viral invasion or occurring as a postinfectious immunologic complication caused by a hypersensitivity reaction... read more occurs sporadically and may be severe. Multiple early seizures are characteristic.

Viral meningitis Viral Meningitis Viral meningitis tends to be less severe than acute bacterial meningitis. Findings include headache, fever, and nuchal rigidity. Diagnosis is by cerebrospinal fluid (CSF) analysis. Treatment... read more may result from HSV-2. It is usually self-limited.

Lumbosacral myeloradiculitis, typically caused by HSV-2, can occur during primary infection or reactivation of HSV-2 infection and can result in urinary retention or obstipation.

Isolated infections often go untreated without consequence.

Acyclovir, valacyclovir, or famciclovir can be used to treat infection, especially when it is primary. Infection with acyclovir-resistant HSV is rare and occurs almost exclusively in immunocompromised patients. Foscarnet may be effective for acyclovir-resistant infections.

Secondary bacterial infections are treated with topical antibiotics (eg, mupirocin or neomycin-bacitracin) or, if severe, with systemic antibiotics (eg, penicillinase-resistant beta-lactams). Systemic analgesics may help.

Gingivostomatitis and pharyngitis may require symptom relief with topical anesthetics (eg, dyclonine, benzocaine, viscous lidocaine). (NOTE: Lidocaine must not be swallowed because it anesthetizes the oropharynx, the hypopharynx, and possibly the epiglottis. Children must be watched for signs of aspiration.) Severe cases can be treated with acyclovir, valacyclovir, or famciclovir.

Herpes labialis responds to oral and topical acyclovir. The duration of a recurrent eruption may be decreased by about a day by applying penciclovir 1% cream every 2 hours while awake for 4 days, beginning during the prodrome or when the first lesion appears. Toxicity appears to be minimal. Famciclovir 1500 mg as one dose or valacyclovir 2 g orally every 12 hours for 1 day can be used to treat recurrent herpes labialis. Acyclovir-resistant strains are resistant to penciclovir, famciclovir, and valacyclovir. Docosanol 10% cream may be effective when used 5 times a day.

Herpetic whitlow heals in 2 to 3 weeks without treatment. Topical acyclovir has not been shown to be effective. Oral or IV acyclovir can be used in immunosuppressed patients and those with severe infection.

Treatment of herpes simplex keratitis Treatment Herpes simplex keratitis is corneal infection with herpes simplex virus. It may involve the iris. Symptoms and signs include foreign body sensation, lacrimation, photophobia, and conjunctival... read more involves topical antivirals, such as trifluridine, and should be supervised by an ophthalmologist.

Acyclovir 20 mg/kg IV every 8 hours for 14 days should be used if renal function is normal. A dose of 20 mg/kg IV every 8 hours for at least 21 days is indicated for CNS and disseminated HSV disease.

Encephalitis is treated with acyclovir 10 mg/kg IV every 8 hours for 14 to 21 days if renal function is normal. Treatment for 14 to 21 days is preferred to prevent potential relapse. Higher doses up to 20 mg/kg IV every 8 hours are used in children.

Viral meningitis is usually treated with IV acyclovir. Acyclovir is generally very well-tolerated. However, adverse effects can include phlebitis, renal dysfunction, and, rarely, neurotoxicity (lethargy, confusion, seizures, coma).