Occurrence and genetic variability of Phlebotomus papatasi in an urban area of southern Italy

Background: A phlebotomine sand fly was noticed in the second floor of an old building in a highly urbanized area of southern Italy. A short-term entomological survey was carried out in the subsequent weeks to this event, allowing the collection of additional phlebotomine sand flies that were later identified as Phlebotomus papatasi. We assessed the genetic variability among P. papatasi sequences obtained in this study and those available from Italy using a mitochondrial DNA (mtDNA) fragment (from cytochrome b gene to NADH1) and the internal transcribed spacer 2 (ITS2) as genetic markers. Results: From 9 June to 19 July, eight males and seven females (two blood-fed) of P. papatasi were collected in the old town of Bari (southern Italy). The insects were found near the bed and in the bathroom and potential blood sources (e.g., pigeons and dogs) for them were common in the neighbourhood. Again, five females of P. papatasi collected in Valenzano, another urban area in the province of Bari, were also identified and included in the genetic study. The mtDNA sequences (945 bp) obtained from Bari and Valenzano were identical except for a single transition (T ↔ C) at the 793 nucleotide residue. Pairwise comparison of the last 440 bp of the mtDNA fragment analyzed herein with other sequences of P. papatasi from Italy revealed a nucleotide variation ranging from 0.2 to 1.3%. Three ITS2 sequence types were detected within specimens collected in Valenzano, one of them identical to that from Bari. Pairwise comparison of ITS2 sequences of P. papatasi from Italy revealed a nucleotide variation up to 1.8%. Conclusions: This study reports the occurrence of P. papatasi in an urban area of southern Italy and shows a low nucleotide difference among ITS2 and mtDNA sequences of this species available from Italy. The presence of P. papatasi in urban areas might represent a risk for human health, particularly for the potential transmission of sandfly fever viruses.