AIMTo study antiviral defense in patients with severe anogenital and labial herpetic infection, prevalence of herpetic infection and possible combination with other strains.MATERIAL AND METHODSThe immune status (basic lymphocyte subpopulations, IgA, IgM, IgG, circulating immune complexes in blood serum, cytokines, interferon status, functional activity of neutrophils) was investigated in 102 patients with severe Herpex simplex infection (HSI).RESULTSMarked deficiency and hyporeactivity of natural and/or specific cytotoxicity were found in 70% HSI patients with severe disease.CONCLUSIONSevere HSI runs in serious combined secondary immunodeficiency, its complications and is an active mixed viral infection.