Only a few data exist about epidemiology, transmission and prevention of hospital-acquired viral infections. In viral infections, all secretions and excretions can be considered contagious in which viruses can multiply or which transport them in the body (i.e. faeces in hepatitis A and infections caused by enteroviruses, serum in hepatitis B, respiratory secretions in respiratory viral infections). Like bacterial infections, viral infections in the hospital are most commonly transferred by hands. Several recently published studies are demonstrated. In addition, guidelines for isolation procedures and disinfection are made.