Genital herpes.

In developed countries, genital herpes is, together with papillomavirus infections, among the most common sexually transmitted diseases. HSV is a dormant virus causing lifelong infection and recurring with or without clinical symptoms. Exposure to lesions and to asymptomatic viral shedding result in transmission. Thus, in most cases, finding the exact path of viral transmission is impossible. The diagnosis is often clinical: classic lesion presentation and typical localised recurrences. The confirmation of the diagnosis is obtained by virus isolation, the most sensitive method is PCR but viral culture techniques are the most widely used. Today, the nucleoside analog antivirals (aciclovir, valacicovir, famciclovir, penciclovir), are the only efficient and well tolerated treatments for genital herpes. The virus resistance to these molecules in immunocompetent patients is very low and has not increased since their introduction. Thus, for these patients, treatment failure is generally due to low bioavailability which is resolved by increasing doses. Ideally a vaccine against herpes should be prophylactic (preventing primary infection) and therapeutic (preventing recurrences). None is available today despite intensive research for the past two decades.