V. M. Chenault1 , M. G. Hodges2 , C. P. Schnupp1 , P. W. Miles3 , V. B. Solberg3 , 1FDA, 2NIH, 3WRAIR
Background: Psammomys obesus is a common rodent in the Middle East. Sand rats (SRs) have been identified as the major reservoir host that transmits Leishmaniasis. Phlebotomine sand flies (SFs) bite humans or other vertebrates to obtain blood proteins for the production of eggs, a necessary step in the transmittal of viruses, bacteria, and protozoa to humans. The volatile outbreak of Leishmaniasis in US troops deployed in Afghanistan and Iraq has caused 28 days of costly treatment for patients. There are no preventive vaccines or prophylactic drugs and the approved healing device is just over 70% effective. Personal Protective Measures have not worked efficaciously. Spraying of insecticides has not controlled SFs. Further, SRs are selective eaters in the wild. Thus, novel adult, pupal and larval control methods must be investigated. These studies were conducted to determine effective endectocide treatment and control methods.
Methods: SRs were fed ivermectin and doramectin treated sand rat chow for 2 weeks. Blood, feces and hair samples were collected to measure the amount of the active ingredients. Body weights were measured to assess food palatability.
Results: The results suggest that endectocide treated food was palatable at levels presumably high enough to kill immature SFs.
Conclusions: Unique precision targeting of rodent reservoir hosts with insecticides applied topically (future studies), or used as endectocides (current study) will provide unprecedented investigations of parasite control. In subsequent studies, treated SRs will be anesthetized and challenged with SFs. Ultimately, therapeutic devices or drugs will be used to investigate treatments.