Twenty-four new human cases of cutaneous leishmaniasis due to Leishmania killicki in Metlaoui, southwestern Tunisia: probable role of Phlebotomus sergenti in the transmission

Abstract

Metlaoui district in the South-west of Tunisia is a classical focus of cutaneous leishmaniasis (CL) due to Leishmania major. Since 2005, a single case of CL due to L. killicki has been reported. We report twenty four human cases due to this parasite, affecting men and women from 2 to 70 years old. Leishmania killicki have been typed using molecular techniques: polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) and gene sequencing. Four strains from patients have been successfully cultured on NNN medium and isoenzymatically typed as L. killicki MON-8. Our results strongly suggests that Metlaoui is a new L. killicki focus with a stable transmission cycle. Sand flies fauna in the same focus was also studied. 1400 Phlebotomine sand flies (785 males/615 females) have been caught during an entomological survey. Leishmania major DNA has been found in one P. papatasi female, the most abundant species, whereas L. killicki DNA has been found in one Phlebotomus sergenti female emphasizing the probable role of this species as vector of this zoonotic parasite.