[Parvovirus B19 infection].

In 1975, during blood screening for hepatitis B, Cossart et al. discovered the human parvovirus B19 (B19). It is a small, single strand DNA virus of the Parvoviridae family. This virus is widespread with 40-80% of adults showing evidence of infection. It is found in the respiratory secretions of viraemic patients and direct contact has been suggested as the most likely mode of transmission. Parenteral transmission is common during treatment with clotting-factor concentrates, but rarely occurs during transfusion with single donor products. Although B19 usually causes a self-limited illness, complications of infection can be severe and at times life threatening. In pregnant women, infection can lead to spontaneous abortions and hydrops fetalis and, in patients with haemolytic anaemias or in immunocompromised individuals, can induce aplastic crisis and chronic anaemias. The diagnosis can be made by indirect (testing for B19 antibodies) or direct methods (detecting B19 viremia). There are no vaccines or specific therapy currently available. Contact isolation is recommended for hospitalized patients.