How do people get infected with Leishmania parasites?
The main route is through the bite of infected female phlebotomine sand flies. Sand flies become infected by sucking blood from an infected animal or person. People might not realize that sand flies are present because:
- They do not make noise when they fly;
- They are small: they are only about one-third the size of typical mosquitoes or even smaller;
- Their bites might not be noticed (the bites may be painless or painful).
Sand flies usually are most active in twilight, evening, and night-time hours (from dusk to dawn). Although sand flies are less active during the hottest time of the day, they may bite if they are disturbed (for example, if a person brushes up against the trunk of a tree or other site where sand flies are resting).
Some types (species) of Leishmania parasites may also be spread by blood transfusions or contaminated needles (needle sharing). Congenital transmission (spread from a pregnant woman to her baby) has been reported.