Enhanced attraction of sand fly vectors of Leishmania infantum to dogs infected with zoonotic visceral leishmaniasis

• Published in: PLoS neglected tropical diseases 2021-07, Vol.15 (7), p.e0009647-e0009647
• Main Authors: Chelbi, Ifhem, Maghraoui, Khouloud, Zhioua, Sami, Cherni, Saifedine, Labidi, Imen, Satoskar, Abhay, Hamilton, James G C, Zhioua, Elyes
• Format: Article
• Language: English
• Subjects: Animals; Behavior; Biology and Life Sciences; Diptera; Dog Diseases; Dog Diseases - parasitology; Dog Diseases - transmission; Dogs; Etiology; Experiments; Fecundity; Feeding Behavior; Feeding Behavior - physiology; Female; Females; Flies as carriers of disease; Health aspects; Host-parasite relationships; Infections; Insect Vectors; Insects as carriers of disease; Kala-azar; Laboratory animals; Leishmania infantum; Leishmaniasis, Visceral; Leishmaniasis, Visceral - parasitology; Leishmaniasis, Visceral - transmission; Leishmaniasis, Visceral - veterinary; Life Sciences; Male; Males; Medicine and Health Sciences; Mortality; Ova; Parasites; Parasitic diseases; People and Places; Pheromones; Phlebotomus; Phlebotomus - physiology; Physiological aspects; Risk factors; Transmission; Tropical diseases; Vaccines; Vector-borne diseases; Vectors; Visceral leishmaniasis; Zoonoses
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0009647

The sand fly Phlebotomus perniciosus is the main vector of Leishmania infantum, etiological agent of zoonotic visceral leishmaniasis in the Western Mediterranean basin. Dogs are the main reservoir host of this disease. The main objective of this study was to determine, under both laboratory and field conditions, if dogs infected with L. infantum, were more attractive to female P. perniciosus than uninfected dogs. We carried out a series of host choice experiments and found that infected dogs were significantly more attractive to P. perniciosus than uninfected dogs in the laboratory as well as in the field. Significantly more P. perniciosus fed on infected dogs than on uninfected dogs. However, the fecundity of P. perniciosus fed on infected dogs was adversely impacted compared to uninfected dogs by lowering the number of laid eggs. Phlebotomus perfiliewi, the second most abundant sand fly species in the field site and a competent vector of L. infantum had similar trends of attractivity as P. perniciosus toward infected dogs under field conditions. The results strongly suggest that L. infantum causes physiological changes in the reservoir host which lead to the host becoming more attractive to both male and female P. perniciosus. These changes are likely to improve the chance of successful transmission because of increased contact with infected hosts and therefore, infected dogs should be particularly targeted in the control of zoonotic visceral leishmaniasis in North Africa.