The group is the Phlebotominae, a subfamily of flies. Parasitic diseases spread by the flies include leishmaniasis, bartonellosis and pappataci fever. In the New World leishmaniasis is spread by sand flies in the genus "Lutzomyia". "Lutzomyia" often live in caves, where their main hosts are bats. In the Old World sand flies in the genus "Phlebotomus" spread leishmaniasis.