Distribution of Phlebotomus perniciosus in North-Italy: A study on 18S rDNA of phlebotomine sand flies

Leishmaniasis has recently spread, and is now endemic, in many parts of North Italy, even if it is not clear how sand flies vectors have reached this area. In order to clarify the origin of the Phlebotomus perniciosus, the main sand flies specie found in these areas, we analyzed and compared the 18S rDNA sequence from 33 out of 122 P. perniciosus collected in new endemic areas, from neighbor (≤120 km) traditionally endemic area (Liguria) and from an area about 400 km far from the North West Italy. Based on the 18S rDNA sequence analysis, three different groups with different degrees of heterogeneity were identified. Two of them are suggestive of migration at a local scale and one, found in all sampled foci, is probably due to passive carriage. Results suggest that both migration on small scale from traditionally endemic area and passive carriage on long distance can contribute to sand flies colonization of new areas.