[Herpes simplex and varicella zoster virus infections].

Herpes simplex virus (HSV) and varicella-zoster virus (VZV) are both human alpha-herpes viruses. They are capable of establishing latent infections in neural tissues and to reactive from these sites, determining the clinical features of the disease (primary infection versus recurrences). Infections with these viruses are common; an increased number of elderly and immunocompromised individuals will likely lead to an even higher prevalence. HSV infection--in its typical form characterized by grouped vesicles--is frequently inapparent or atypical in both primary and recurrent disease. The clinical spectrum is wide, ranging from trivial labial blisters to the most severe fatal sporadic encephalitis and neonatal infection. Seroprevalence studies in the Western world demonstrate a much higher percentage of people infected with HSV-2 than are currently identified by clinical studies. Since undiagnosed genital herpes infections are the major factor in fueling the genital herpes epidemic, awareness and more accurate diagnosis followed by therapy and counseling are mandatory. Primary VZV infection and herpes zoster are usually diagnosed clinically, but can be confirmed by virus detection methods from swabs of lesions or antibody tests. Antiviral therapy should be considered in varicella if the disease is complicated. In herpes zoster antiviral therapy should be given within 72 hours in immunocompromised patients and those at risk of postherpetic neuralgia. The availability of effective antiviral therapy makes early diagnosis most important.