[Viral infections in immunocompromised patients]

An increasing number of patients are immunocompromised due to modern treatment of cancer, organ transplantations and HIV-infections. Opportunistic viral infections are common and may cause serious disease among these patients. New vaccines, immunomodulators and antiviral drugs make it possible to prevent and treat many of these infections. We review the host defence against viral infections and the most important viral infections. We also discuss prophylaxis, diagnosis and therapy.