Experimental Transmission of Leishmania mexicana to Hamsters by Bites of Phlebotomine Sand Flies (Diptera: Psychodidae) from the United States1

Laboratory-reared Lutzomyia diabolica (Hall) and Lutzomyia shannoni (Dyar), the only known anthropophilic sand flies occurring in the United States, transmitted Leishmania mexicana Biagi by bite to Syrian hamsters. The parasite strain (MHOM/US/80/WR-411) was originally isolated from a human patient living in Uvalde, Tex. Eighty-eight percent of 523 L. diabolica and 95% of 173 L. shannoni became infected after feeding on leishmanial histiocytomas of experimentally infected hamsters. At least 6% of the L. diabolica and 12% of the L. shannoni refed on uninfected hamsters 3–14 d after the infecting blood meal. Five of 21 hamsters fed upon by one or more L. diabolica and five of five hamsters fed upon by L. shannoni developed cutaneous lesions 14–148 d after the transmitting bite(s).