Abstract
Globally visceral leishmaniasis (VL) causes thousands of human deaths every year. In South America, the etiologic agent, Leishmania infantum, is transmitted from an infected canine reservoir to human hosts by the bite of the sand fly vector; predominantly Lutzomyia longipalpis. Previous evidence from model rodent systems have suggested that the odour of infected hosts is altered by the parasite making them more attractive to the vector leading to an increased biting rate and improved transmission prospects for the pathogen. However, there has been no assessment of the effect of Le infantum infection on the attractiveness of dogs, which are the natural reservoirs for human infection. Hair collected from infected and uninfected dogs residing in a VL endemic city in Brazil was entrained to collect the volatile chemical odours present in the headspace. Female and male Lu. longipalpis sand flies were offered a choice of odour entrained from infected and uninfected dogs in a series of behavioural experiments. Odour of uninfected dogs was equally attractive to male or female Lu. longipalpis when compared to a solvent control. Female Lu. longipalpis were significantly more attracted to infected dog odour than uninfected dog odour in all 15 experimental replicates (average 45.7±0.87 females attracted to infected odour; 23.9±0.82 to uninfected odour; paired T-test, P = 0.000). Male Lu. longipalpis did not significantly prefer either infected or uninfected odour (average 36.1±0.4 males to infected odour; 35.7±0.6 to uninfected odour; paired T-test, P = 0.722). A significantly greater proportion of females chose the infected dog odour compared to the males (paired T-test, P = 0.000). The results showed that the odour of dogs infected with Le. infantum was significantly more attractive to blood-seeking female sand flies than it was to male sand flies. This is strong evidence for parasite manipulation of the host odour in a natural transmission system and indicates that infected dogs may have a disproportionate significance in maintaining infection in the canine and human population.
Funder
Lancaster University, Division of Biomedical and Life Sciences
Wellcome Trust
Publisher
Public Library of Science (PLoS)
Subject
Virology,Genetics,Molecular Biology,Immunology,Microbiology,Parasitology
Reference69 articles.
1. Phlebotominae sandflies and the spreading of leishmaniases and other diseases of public health concern;M Maroli;Medical and Veterinary Entomology,2013
2. Leishmaniasis;S Burza;The Lancet,2018
3. Leishmaniasis worldwide and global estimates of its incidence;J Alvar;PlOS One,2012
4. WHO. Leishmaniasis Geneva: World Health Organisation; 2020 [updated 30 November 202005 May 2020]. Available from: https://www.who.int/en/news-room/fact-sheets/detail/leishmaniasis.
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