An investigation into the clinical and laboratory features of an outbreak of 31 cases of anicteric leptospirosis.

THE first case of leptospirosis in Malaya was encountered by Fletcher in 1925, when he was investigating the' isolation of Rickettsice from cases of fever of unknown origin. Galloway (1926) described four icteric cases with a very severe clinical picture. Fletcher (1928) reported 32 cases investigated at Kuala Lumpur. Since then the disease has been recognized increasingly throughout the country, and cases have been described by Lewthwaite (1929) and Danaraj (1950). A limited serum survey of members of the civil population has shown evidence of infection in a quarter of those tested (Wisseman et. al.; 1955). Leptospirosis has been one of the hazards facing security forces engaged in jungle warfare (Broom, 1953),' and has also achieved military importance elsewhere in the Far East (de la Judie & Brygoo, 1953). The purpose of this paper is to describe the clinical and laboratory investigations performed on 31 cases of leptospirosis admitted to a British Military Hospital in Malaya at the end of 1953. All the patients were from the same British Army unit and were engaged on routine security operations mainly in primary jungle. Of the 31 cases, 29 were proved by either cultural or serological methods to be leptospirosis. The remaining 2 cases had such typical clinical and laboratory features as to make the diagnosis very probable.