Blood meal survey reveals insights into mosquito-borne diseases on the island of Santiago, Cape Verde

Abstract

IntroductionThe transmission of pathogens by blood-sucking insects to humans and other animals depends on vector-host interactions. As yet unexplored in Cape Verde, mosquito feeding behavior plays a crucial role in pathogen transmission. Herein, we aim to explore, through blood meal analysis, the relationship between mosquito species and common hosts in Santiago Island, Cape Verde.MethodsEngorged female mosquitoes were collected through mechanical aspiration from May 2016 to December 2017 in three municipalities of Santiago Island (Praia, Santa Cruz, and Santa Catarina). Blood-feeding behavior in each municipality was assessed through blood meal analysis using an enzyme-linked immunosorbent assay (ELISA).ResultsWe were able to determine that single-host blood meals were common in Aedes aegypti, Anopheles arabiensis, and Culex pipiens sensu lato (s.l.). In general, the mosquitoes preferred to feed on humans, dogs, and chickens, and on multiple hosts, mainly two hosts. The human blood index (HBI) was highest (i.e., 1.00) in Ae. aegypti, with the lowest value (0.40) observed in An. arabiensis. It was observed that, among single-host blood meals, the likelihood of Cx. pipiens s.l. feeding on humans was significantly high, whereas the likelihood of An. arabiensis feeding on humans was significantly low (log-odds ratio (LOR) = 0.85 and –2.44, respectively). In addition, a high likelihood of Ae. aegypti feeding on humans was observed, but this was not statistically significant (LOR = 0.85).DiscussionOverall, our findings demonstrate a lack of feeding preference in Culex pipiens s.l. compared with Ae. aegypti and An. arabiensis. These results provide insights into possible parasite transmission and pathogen spillover/spillback, which threaten human/animal health and the economy in Cape Verde.