Phlebotomus fever, also commonly called pappataci or sandfly fever, is a specific febrile disease of virus etiology which is of considerable military importance because of its occurrence in many parts of the world where troops are stationed. The adult native populations are for the most part immune, but when troops or other people from areas where the disease is not prevalent move into endemic zones they succumb in large numbers. While the disease is self limited and there are no fatalities, its military importance lies in the fact that it can incapacitate large numbers of men for periods of seven to fourteen days or longer at a time when their services may be needed most. The clinical picture of Phlebotomus fever resembles that of influenza but without the signs of acute inflammation of the respiratory tract which commonly accompany the latter disease. It is characterized by fever ranging from 100