Mitochondrial and Wolbachia markers for the sandfly Phlebotomus papatasi: little population differentiation between peridomestic sites and gerbil burrows in Isfahan province, Iran

Abstract

In Iran, Phlebotomus papatasi (Scopoli) (Diptera: Psychodidae) is the main vector of Leishmania major Yakimoff & Schokhor (Kinetoplastida: Trypanosomatidae), the causative agent of rural zoonotic cutaneous leishmaniasis. This sandfly is abundant both in villages and in the burrows of the main reservoir host, the gerbil Rhombomys opimus (Licht.) (Rodentia: Gerbillidae). Populations of P. papatasi were sampled from the edges of villages in Isfahan province, using CDC miniature light traps in peridomestic sites and sticky papers placed at the entrances to gerbil burrows. Single peridomestic sites in two northern provinces were also sampled. Individual sandflies were characterized by PCR amplification and sequencing of fragments of their mitochondrial cytochrome b gene and of the wsp gene of endosymbiotic Wolbachia pipientis Hertig (alpha-Proteobacteria: Rickettsiaceae). The distributions of the haplotypes of these two maternally inherited genes were analysed to assess the population differentiation of P. papatasi, knowledge of which will be needed for planning control measures. For the first time these markers were used to characterize P. papatasi from gerbil burrows, and they indicated the absence not only of sympatric cryptic species but also of any long-term differentiation of lineages in different habitats. A single lineage of cytochrome b haplotypes was found, and both sexes in all populations had a high infection rate of the same A-group strain of Wolbachia (wPap). The distributions of cytochrome b haplotypes were consistent with females dispersing more than males, which has been reported for P. papatasi in other countries. The widespread distribution of wPap suggests that Wolbachia could be used to spread transgenes between populations of P. papatasi in different habitats.