Preliminary Observations on a Repellent for Terrestrial Leeches

Abstract

INCIDENTAL to studies on the natural history of leptospirosis and scrub typhus, members of a joint U.S. Army–British Colonial Office Research Team, operating recently under field-conditions in North Borneo, noted that a new U.S. Army repellent (M-1960), used for impregnating clothing against mites, mosquitoes and fleas, was exerting a highly repellent effect against terrestrial leeches. This repellent, developed by the United States Department of Agriculture, in a project financed by the Department of the Army, is being made a standard item of issue for the U.S. Army and is known as “Repellent, insect, clothing-treatment, M-1960”. It consists of equal parts of N-butyl acetanilide, 2-butyl-2 ethyl-1,3-propanediol, and benzyl benzoate, with 10 per cent of emulsifying agent (‘Tween 80’). One gallon of the concentrate is enough to treat 28 uniforms after emulsification. Preliminary observations on its effect on leeches are reported here.