Page:Tropical Diseases.djvu/346



Definition.— A specific fever of short duration and no mortality, caused by a germ— ultramicroscopic—introduced by the bite of the sand-fly (phlebotomus).

History.— This disease has been recognized clinically for upwards of a century and described under a variety of local names; but its definite relation to its transmitting agent, although suspected by McCarrison (if his three days' fever of Chitral be the same) in 1903 and by Taussig in 1905, was not established till 1908, when Doerr published his observations of the infectivity of the blood in this form of fever and the role of the sand-fly as transmitter. Doerr's conclusions have been confirmed by numerous observers in Malta and elsewhere around the Mediterranean, including Kilroy. Kilroy exposed himself for five nights to the bites of sand-flies on Suda Island, where these insects are particularly abundant and where phlebotomus fever is prevalent; subsequently, at the end of the first day of his fever, he injected his blood into a healthy man and thereby communicated the disease.

Geographical and seasonal distribution.— The range of phlebotomus fever is probably co-extensive with that of the insect transmitter. In the tropics it may break out at any time as an epidemic amongst new arrivals; in the sub-tropics it occurs only or principally during the summer and early autumn. Where the phlebotomus is absent, e.g.Bermuda (Birt), the fever is not found. In some phlebotomus-haunted places as many as 50 per cent, of new-comers are attacked.

Etiology.— The germ resides in the blood of the patient during the first day or two of the fever. It is ultramicroscopic, passing through filters