Vector

Transmission of parasite occurs by the female sandflies, Phlebotomus in the old world and Lutzomyia in the new world. Although there are more than 600 known species of sandflies, only about 10% of these transmit Leishmania. A fly remain infected for life, however, less than 1% of sandflies in the endemic areas are infected. Sandfly normally feeds on fruits and bark of certain trees. The female sandfly needs to feed on blood to hatch eggs. They suck blood from both animals and humans. Most species bite at night and at dusk. They are small in size (~2mm in length) and can pass through the routinely used mosquito nets. Impregnated nets can protect biting as the permethrin (insecticide) can kill the sand fly while trying to pass through the net and is thus recommended to use impregnated bed nets. Sandflies are poor flyers, remain low and in the vicinity of their breeding site. They do not fly when there is wind. Because of the very short mouth parts, they cannot bite through clothing. They bite exposed parts of the body usually face and hands. Their body and wings are hairy and keep their wings in V shape upright above them at rest. They require high temperature and humidity for breeding; thus, microclimates like crevices, termite hills, caves, hollows and holes in tree roots are favorable environments. Poor household infrastructure, ruins of houses, bushy areas can be breeding and resting habitats for the sandfly. People living in close proximity with such conditions are at risk for infection. This knowledge can be used in the insect control part of the disease prevention and control.

The species identified for the transmission of L donovani in Ethiopia are P orientalis in the northern part, and P martini and P celiae in the southern part of the country.