Detection of Leishmania DNA and blood meal sources in phlebotomine sand flies (Diptera: Psychodidae) in western of Spain: Update on distribution and risk factors associated.

Leishmaniosis caused by Leishmania infantum is present in Mediterranean countries, with high prevalence in areas of the center and south of Spain. However, in some regions such as Extremadura (in southwest of Spain), data has not been updated since 1997. The aim of this work was (i) to provide information about the distribution of phlebotomine sand fly species in western of Spain (Extremadura region), (ii) to determine risk factors for the presence of sand fly vectors and (iii) to detect Leishmania DNA and identify blood meal sources in wild caught females. During 2012-2013, sand flies were surveyed using CDC miniature light-traps in 13 of 20 counties in Extremadura. Specimens were identified morphologically and females were used for molecular detection of Leishmania DNA by kDNA, ITS-1 and cyt-B. In addition, blood meals origins were analyzed by a PCR based in vertebrate cyt b gene. A total of 1083 sand flies of both gender were captured and identified. Five species were collected, Phlebotomus perniciosus (60.76%), Sergentomyia minuta (29.92%), P. ariasi (7.11%), P. papatasi (1.48%) and P. sergenti (0.74%). The last three species constitute the first report in Badajoz, the most southern province of Extremadura region. Leishmania DNA was detected in three out of 435 females (one P. pernicious and two S. minuta). Characterization of obtained DNA sequences by phylogenetic analyses revealed close relatedness with Leishmania tarentolae in S. minuta and L. infantum in P. perniciosus. Haematic preferences showed a wide range of hosts, namely: swine, humans, sheep, rabbits, horses, donkeys and turkeys. The simultaneous presence of P. perniciosus and P. ariasi vectors, the analysis of blood meals, together with the detection of L. infantum and in S. minuta of L. tarentolae, confirms the ideal conditions for the transmission of this parasitosis in the western of Spain. These results improve the epidemiological knowledge of leishmaniosis and its vectors in this part of Spain, highlighting the need for ongoing entomological and parasitological surveillance.