An alternative approach to detect Trypanosoma in Glossina (Diptera, Glossinidae) without dissection.

BACKGROUND: Determining if a tsetse fly is infected by trypanosomes and thus potentially able to transmit trypanosome-related human and animal diseases is an extremely laborious and time-consuming task to perform, especially under field conditions. In this study we tested a possible alternative approach that uses the entire insect vector for DNA extraction and PCR analysis to detect and identify Trypanosoma spp. in field collected tsetse flies. METHODOLOGY: DNA extraction was performed using a method originally developed for tick DNA extraction followed by PCR detection and identification of Trypanosoma spp. RESULTS: Two out of 62 flies captured in Equatorial Guinea carried DNA of T. brucei s.l. and Trypanosoma vivax. T. congolense forest, T. congolense savannah and T. congolense Kilifi were not detected. CONCLUSIONS: The approach we employed allowed the molecular detection and species identification of trypanosomes using the whole vector body for DNA extraction. Although the approach does not give direct information on tsetse infectivity, it provides valuable information about trypanosome species circulating in a tsetse fly vector population. The method allows an effective processing of a large number of field captured tsetse in a central laboratory.