Identification of trypanosomatids and blood feeding preferences of phlebotomine sand fly species common in Sicily, Southern Italy

PLoS One. 2020 Mar 10;15(3):e0229536. doi: 10.1371/journal.pone.0229536. eCollection 2020.

Abstract

In this study, the presence of Leishmania DNA and blood feeding sources in phlebotomine sand fly species commonly present in Sicily were investigated. A total of 1,866 female sand flies including 176 blood fed specimens were sampled over two seasons in five selected sites in Sicily (southern Italy). Sergentomyia minuta (n = 1,264) and Phlebotomus perniciousus (n = 594) were the most abundant species at all the sites, while three other species from the genus Phlebotomus (i.e., P. sergenti n = 4, P. perfiliewi n = 3 and P. neglectus n = 1) were only sporadically captured. Twenty-eight out of the 1,866 (1.5%) sand flies tested positive for Leishmania spp. Leishmania tarentolae DNA was identified in 26 specimens of S. minuta, while the DNA of Leishmania donovani complex was detected in a single specimen each of S. minuta and P. perniciosus. Interestingly, seven S. minuta specimens (0.4%) tested positive for reptilian Trypanosoma sp. Blood sources were successfully identified in 108 out of 176 blood fed females. Twenty-seven out of 82 blood sources identified in fed females of P. perniciosus were represented by blood of wild rabbit, S. minuta mainly fed on humans (16/25), while the sole P. sergenti fed specimen took a blood meal on rat. Other vertebrate hosts including horse, goat, pig, dog, chicken, cow, cat and donkey were recognized as blood sources for P. perniciosus and S. minuta, and, surprisingly, no reptilian blood was identified in blood-fed S. minuta specimens. Results of this study agree with the well-known role of P. perniciosus as vector of L. infantum in the western Mediterranean; also, vector feeding preferences herein described support the hypothesis on the involvement of lagomorphs as sylvatic reservoirs of Leishmania. The detection of L. donovani complex in S. minuta, together with the anthropophilic feeding-behaviour herein observed, warrants further research to clarify the capacity of this species in the transmission of pathogens to humans and other animals.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • DNA / genetics
  • Feeding Behavior
  • Insect Vectors
  • Leishmania / genetics
  • Psychodidae / classification
  • Psychodidae / genetics*
  • Psychodidae / pathogenicity*
  • Seasons
  • Sicily
  • Species Specificity
  • Trypanosomatina / genetics

Substances

  • DNA

Grants and funding

Sand fly collection in 2018 season has been partially funded by Bayer Animal Health. The founder did not play any role in the study design, data collection and analysis, decision to publish and preparation of the manuscript. Molecular analysis on sand flies were partially founded by the grant Research and Mobility no.015063 awarded by the University of Messina. Dr Carla Maia has been awarded with Investigator Starting Grant F/01302/2015, and André Pereira received PhD grant SFRH/BD/116516/2016. Bayer Animal Health provided support in the form of salaries for authors [MP], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.”