Parvovirus B19

Abstract

Parvovirus B19 (B19V) is a small DNA virus that replicates in erythroid progenitor cells, with virus-induced cytotoxicity stopping red cell production. It only infects humans, is endemic in most places, and is transmitted predominantly by the respiratory route. In healthy people it causes the rash illness, erythema infectiosum, also known as ‘fifth disease’ or ‘slapped cheek disease’, associated with minimal drop in haemoglobin, but in patients with increased red cell turnover (e.g. haemolytic anaemia or haemoglobinopathy), it causes transient aplastic crisis; in immunocompromised patients it causes chronic anaemia; and following maternal infection it leads to hydrops fetalis or fetal loss. Treatment is supportive in most instances, but reduction in iatrogenic immunosuppression and/or intravenous immunoglobulin may be appropriate in some cases. No vaccine is available.