Sandflies species composition, activity, and natural infection with Leishmania, parasite identity in lesion isolates of cutaneous leishmaniasis, central Iran

Zoonotic cutaneous leishmaniosis (ZCL) is a crucial public health challenge in Iran. Sandflies feed on reservoir rodents’ blood infected with Leishmania parasite and transmit it to other hosts. This study was conducted to find out the composition and monthly activity of sandflies as well as to identify the protozoan pathogens (Leishmania/Crithidia) by polymerase chain reaction (PCR) in an emerging ZCL focus of Abarkooh, Yazd province, Iran, in 2016. A cross-sectional study was done in rural areas of Abarkooh. From April to November 2016, sticky traps were used indoor and outdoor to capture sandflies once every fortnight. Their composition and monthly activity were recorded. Following identification of sandflies and DNA extraction from them, PCR was used to identify their parasite and match it against samples taken from ZCL confirmed and suspected patients’ lesions. After collection, a total of 2045 sandflies (779 indoor, 1266 outdoor) were identified to species level. Sandfly activity started early April in this area with two active peaks (one late May and the other late August) terminated about mid-November. Seven Phlebotomus species and three Sergentomyia species were identified. The most and the least abundant species were P. papatasi (40.1%) and P. alexandri (0.09%), respectively. Using PCR, only 6% (12:200) of P. papatasi sandflies were infected with Leishmania parasite. No Crithidia was detected in either sandflies or human lesions (176 specimen). Based on the highest abundance both indoor and outdoor of P. papatasi, this sandfly was considered the main vector of ZCL in this area. The capture of P. caucasicus, P. mongolensis, and P. ansarii from rodent burrows showed these species were likely involved in pathogen transmission in reservoir rodents’ burrows.