Rabbit trypanosome detection in Phlebotomus perniciosus sand flies from the leishmaniasis outbreak in Madrid, Spain

Abstract

Phlebotomine sand flies are known vectors of several pathogens. In Spain, Phlebotomus perniciosus and Phlebotomus ariasi are the proven vectors of Leishmania infantum. Since 2010 a human leishmaniasis outbreak has been notified in Madrid region, central Spain. Studies have shown that P. perniciosus is the only vector confirmed in the focus area and that rabbits and hares are the wild reservoirs incriminated in the cycle of the parasite in the outbreak. Trypanosoma nabiasi is a trypanosomatid found in wild rabbits and its presence has been reported in wild rabbits from southern Spain. Moreover, co-infection with L. infantum was found in some of these animals. However, in Madrid region, there is no information about the transmission of this trypanosome in rabbits. Hence, in this study we investigate if T. nabiasi could be circulating in the aforementioned leishmaniasis focus. Wild P. perniciosus female sand flies were captured in the affected area and analyzed using molecular methods. T. nabiasi DNA was detected in 20 out of 155 female sand flies fed on rabbits by amplification and subsequent sequencing of ITS1 and SSU rRNA fragments. Therefore, we describe for the first time the presence of T. nabiasi and its co-infection with L. infantum in P. perniciosus female sand flies. More investigation is needed in order to elucidate the role of P. perniciosus in the transmission of T. nabiasi among rabbits and its potential consequences.