Dictionary of Tropical Medicine

Weil-Felix Test

An agglutination test used in the laboratory to diagnose rickettsial diseases. It depends on a non-specific cross reaction between antibodies produced by the rickettsial infection with the OX-2, OX-19 and OXK antigens of the Gram negative rod, Proteus.

Weils Disease

Epidemic jaundice. A severe form of leptospirosis caused by such serovars as Leptospira icterrohaemorrhagiae.

Widal Test

A serological test used to detect antibodies in the diagnosis of typhoid. Antigens detected are the O (somatic), H (flagellar) and Vi (virulence) antigens.

Winterbottoms Sign

A posterior cervical lymphadenopathy indicative of early West African (Gambian) Sleeping Sickness due to Trypanosoma brucei gambiense.

Wrights stain

One of the Romanowski stains used to stain blood films and blood parasites such as those causing relapsing fever, malaria trypanosomiasis and filariasis.