Comparison of in vivo and in vitro methods for blood feeding of Phlebotomus papatasi (Diptera: Psychodidae) in the laboratory

Authors: DENLINGER, DAVID - Utah State University; DURHAM, SUSAN - Utah State University; Li, Andrew; LAWYER, PHILIP - National Institutes Of Health (NIH); ANDERSEN, JOSEPH - Utah State University; BERNHARDT, SCOTT - Utah State University

Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/23/2016
Publication Date: 6/12/2016
Citation: Denlinger, D.S., Durham, S., Li, A.Y., Lawyer, P.G., Andersen, J.L., Bernhardt, S.A. 2016. Comparison of in vivo and in vitro methods for blood feeding of Phlebotomus papatasi (Diptera: Psychodidae) in the laboratory. Journal of Medical Entomology. 53(5):1112-1116.

Interpretive Summary: Phlebotomine sand flies are blood-feeding insects that transmit pathogens causing Leishmaniasis affecting people in many countries, and also pose a significant threat to U.S. military personnel when deployed to the Middle East and Africa where those disease vectors are endemic. The establishment of laboratory colonies is critical for understanding the biology of arthropods that vector disease agents. Researchers using laboratory colonies of sand flies have been able to study sand fly physiology, insecticide efficacy, disease transmission, and vaccine development. Laboratory maintenance of sand fly colonies requires a large number of rodents (e.g. mice, hamsters, guinea pigs) to meet the sand fly blood feeding demands. The high cost and maintenance of rodents have advocated for alternative blood-feeding methods to be investigated. A team of researchers from Utah State University, USDA, and NIH conducted a project to evaluate the utilities of two in vitro membrane feeding systems in blood feeding of the old world sand fly species, Phlebotomus papatasi. Results indicate female sand flies blood fed consistently and successfully through the glass feeder with hog’s gut membrane and the Hemotek feeder with Parafilm membrane. Results of this study validated those in vitro sand fly membrane feeding systems as useful alternatives to live animals (rodents) in blood feeding of the laboratory colonies of this sand fly species. The results are of interest to sand fly researchers, public health professionals, pest control managers concerned with sand fly bites and Leishmaniasis.

Technical Abstract: Phlebotomus papatasi Scopoli is a medically-important insect that been successfully colonized in the laboratory, and blood-feeding is critical for colony propagation. There has been much interest in developing established protocols for artificial blood-feeding systems. The objective of this study was to determine if a Parafilm membrane and a hog’s gut membrane could be successfully used with artificial feeding systems. We evaluated proportions of P. papatasi females that blood-fed on different blood-feeding systems (a mouse, a Hemotek feeder, and a glass feeder) used with either a Parafilm or hog’s gut membrane, with cohorts of 250 and 500 P. papatasi females, and with or without external exhalations. Exhalations significantly increased the proportion of female P. papatasi that blood-fed with the Hemotek system and a hog’s gut membrane (P < 0.0001) and a Parafilm membrane (P < 0.0001). With 500 females, a larger mean proportion of female P. papatasi fed with the glass feeder:hog’s gut membrane (P = 0.0297), the Hemotek:Parafilm membrane (P = 0.0066), and with a mouse (P = 0.0460). This suggests that female P. papatasi may use an invitation effect to blood-feed, which has been characterized in other blood-feeding arthropods. We demonstrate that a Parafilm membrane and a hog’s gut membrane, with the Hemotek feeding system and/or glass feeder system, can consistently and successfully blood-feed a colony of P. papatasi