[New knowledge regarding herpes zoster]

Zoster is the clinical manifestation of the endogenous reactivation of the varicella-zoster virus. Current observations of viral reactivation emphasize the role of cellular immunity and show an inverse correlation between the specific cellular immune response of the host and the incidence of zoster. Thus, immunocompromised persons like patients with immune deficiency syndrome, lymphoproliferative cancer, or immunosuppressive therapy are at a high risk for the development of disseminated zoster, which may either involve the skin only, or affect more than one organ. During the last few years zoster has been proved a prognostic marker for HIV-positive persons. The incidence of zoster and post-zoster neuralgia increases with advancing age. In young children, immunosuppressive therapy and varicella in utero or during the first year of life are the only risk factors for zoster infection. Prevention of dissemination has been one of the major goals in antiviral chemotherapy of zoster in immunocompromised patients. Among the antiviral drugs available at present, aciclovir has proved especially useful, acting as an inhibitor of viral DNA polymerase. It is well-tolerated and can be applied together with corticoids, analgetics, and retrovir. It is most effective in reducing complications of zoster.