infectious diseases
Herpes Simplex Virus (HSV) Infections
Introduction
Herpes simplex viruses (human herpesviruses types 1 and 2) commonly cause recurrent infection affecting the skin, mouth, lips, eyes, and genitals. Common severe infections include encephalitis, meningitis, neonatal herpes, and, in patients who are immunocompromised, disseminated infection. Mucocutaneous infections cause clusters of small painful vesicles on an erythematous base. Diagnosis is clinical; laboratory confirmation by culture, polymerase chain reaction, direct immunofluorescence, or serologic testing can be done. Treatment is symptomatic; antiviral therapy withacyclovir,valacyclovir, orfamcicloviris helpful for severe infections and, if begun early, for recurrent or primary infections. Eight types of herpesviruses infect humans, two of which are herpes simplex viruses (HSV). Both types of herpes simplex virus, HSV-1 and HSV-2, can cause oral or genital infection. Most often, HSV-1 causes gingivostomatitis, herpes labialis, and herpes keratitis. HSV-2 usually causes genital lesions. (See Overview of Herpesvirus Infections .) Transmission of HSV results from close contact with a person who is actively shedding virus. Viral shedding occurs from lesions but can occur even when lesions are not apparent. After the initial infection, HSV remains dormant in nerve ganglia, from which it can periodically reactivate, causing symptoms. Recurrent herpetic eruptions are precipitated by Overexposure to sunlight Febrile illnesses Physical or emotional stress Immunosuppression Unknown stimuli Generally, recurrent eruptions are less severe and occur less frequently over time. 