Aplastic crisis and other effects of the human parvovirus infection.

Human parvovirus infections are common, provoke aplastic crises in patients with congenital haemolytic anaemia and cause fifth disease. An unknown proportion of the infections are subclinical. Parvoviraemia occurs in the early acute stage of infection and specific IgM can be detected during recovery. Most patients commencing an aplastic crisis are viraemic, but fifth disease arises after the viraemia. Serological tests for HPV, available at a small but increasing number of laboratories, will soon be complemented by tests for HPV DNA sequences present in blood, marrow and at other sites. Human parvovirus infection is occasionally fatal in patients with severe forms of congenital haemolytic anaemias and further study may reveal other unusual serious consequences of this ubiquitous infection. Short-term protection of vulnerable patients may be achievable with normal immunoglobulin, but there are still considerable obstacles to the preparation and use of a human parvovirus vaccine.