HIV Topics 
Viral Infections
Herpes Simplex (HSV) Infection
HSV is transmitted as vertical transmission and horizontal transmission through direct contact infected oral secretions or lesions. Vertical transmission occurs predominantly intrapartum when the fetus passes through the birth canal and is exposed to genital ulcer. Caesarean section lowers the risk of transmission (65, 66). Neonatal infections are usually caused by HSV type 2.
Clinical features
Recurrent or persistent HSV infection is an AIDS indicating condition.
Neonatal HSV leads to CNS involvement or involves skin, eyes and mouth. Vesicular rash is seen. Outside the neonatal period, the most common manifestation is extensive ulcers in and around the mouth which are painful 4-5 mm in diameter and can be seen on tongue, lips and all mucosal surfaces (Gingivostomatitis). Other sites such as esophagus, CNS, genitals and systemic disease may occur.
Diagnosis
Typical ulcers lead to a clinical diagnosis. The virus can be isolated in culture and detected in tissue culture cells with 1-3 days. Giemsa staining (Tzanck smear) of lesion cell scraping may show multinucleated giant cells and eosinophilic intranuclear inclusion, but this does not differentiate HSV from varicella zoster infection and is not routinely recommended. Detection of HSV 1 & 2 antigens from skin or mucosal scrapings by immunoflorescent techniques aids in diagnosis. In patients with suspected HSV encephalitis, detection of HSV DNA by PCR is the diagnosis of choice. Rising antibody titres of HSV 1 & 2 IgG is also useful.
Treatment
Acyclovir is the drug of choice. Neonatal HSV should be treated with IV acyclovir (20 mg/kg/do tds) for 21 days for CNS disease and 14 days for skin, eye and mouth disease. Disseminated HSV or encephalitis outside the neonatal period should receive IV Acyclovir (10 mg/kg/dose tds) for 21 days. Patients with gingivostomatitis should be treated with IV Acyclovir (5-10 mg/kg/dose tds) or oral acyclovir (20 mg/kg/dose tds) for 7-14 days. Among HIV infected children with acyclovir-resistant HSV, intravenous foscarnet (120 mg/kg/day in 2-3 divided doses) is useful. It should be given till infection resolves. Valacyclovir is a prodrug of acyclovir with increased bioavailability and approved for use in adolescents for treatment of genital herpes at dose of 1 gm twice daily for 7-10 days. Famciclovir is approved for treatment of recurrent mucocutaneous HSV in HIV infected adolescents at dose of 500 mg orally twice daily for 7 days.
Prophylaxis
Primary prophylaxis : Antiviral prophylaxis after exposure to HSV or to prevent initial episodes of HSV disease in patients with latent infection is not recommended.
Secondary prophylaxis : Patients with frequent or severe recurrences can be given daily suppressive therapy with oral acyclovir (80 mg/kg/day in 3-4 doses PO)
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