Human parvovirus B19

Human parvovirus B19 belongs to the family Parvoviridae and is the only recognised human member of the family. It was first discovered in 1982 when serum specimens were being examined in the electron microscope for the presence of hepatitis B surface antigen. At first no disease could be associated with the 20 nm icosahedral particles, but it was soon realised that they were the cause of the acute childhood infection called ‘fifth disease’ or erythema infectiosum or, in lay terms ‘slapped cheek syndrome’. This is a mild infection characterised by a transient lacey rash which spreads centrifugally from the face to the arms and legs. The rash is preceded by a prodrome of sore throat and fever and is frequently followed by arthralgia, particularly of the small joints of the hands and feet and most painful and prolonged in middle-aged women.