Increased prevalence of human cutaneous leishmaniasis in Israel and the Palestinian Authority caused by the recent emergence of a population of genetically similar strains of Leishmania tropica

Importation during numerous migrations of humans and, perhaps, infected reservoir animals in the past and, now, through modern travel is the most likely explanation for the existence of so many locally encountered genetic variants of L. tropica in the Israeli-Palestinian region. Geographical and ecological variation may play a role in expanding the genetic heterogeneity once given importations had become established in different foci. Currently, one population is expanding in the area comprising almost all of the Palestinian and Israeli strains of L. tropica isolated since 1996 and investigated in this study, which differ clearly from all other strains of whatsoever origin. This population seems to result from the re-emergence of a previously existing genotype owing to environmental changes and human activities.