Blood meal source and mixed blood-feeding influence gut bacterial community composition in Aedes aegypti

Authors: Muturi, Ephantus; NJOROGE, TERESIA - University Of Illinois; Dunlap, Christopher; CACERES, CARLA - University Of Illinois

Submitted to: Parasites & Vectors
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/1/2021
Publication Date: 1/28/2021
Citation: Muturi, E.J., Njoroge, T.M., Dunlap, C.A., Caceres, C.E. 2021. Blood meal source and mixed blood-feeding influence gut bacterial community composition in Aedes aegypti. Parasites & Vectors. 14. Article 83 https://doi.org/10.1186/s13071-021-04579-8.
DOI: https://doi.org/10.1186/s13071-021-04579-8

Interpretive Summary: The mosquito gut hosts a dynamic microbial community that influences host health. Some members of this microbial community reduce mosquito ability to transmit diseases and are currently being investigated as potential tools for controlling mosquito-borne diseases. Unraveling the composition of these microbial communities and the factors that influence their composition is an important step towards their future application in mosquito-borne disease control. Females of many mosquito species take blood as part of their diet, and it is common for a single mosquito to obtain a blood meal from multiple animal species. This study examined how a mosquito feeding on blood from more than one animal species affects the composition of microbial communities in the mosquito gut. The results show that mosquitoes fed on a mixture of blood from two animal species had different gut bacterial communities compared to mosquitoes fed on blood from one animal species. These findings demonstrate that the gut microbial communities within the vector midgut shift in response to mixed blood feeding and could potentially alter the ability of the mosquito to transmit diseases.

Technical Abstract: The guts of blood-sucking insects host a community of bacteria that can shift dramatically in response to biotic and abiotic factors. Identifying the key factors structuring these microbial communities has important ecological and epidemiological implications. We used the yellow fever mosquito, Aedes aegypti to investigate the impact of mixed blood meals on gut microbiota of vector mosquitoes. Adult females were experimentally fed on sugar or blood from chicken, rabbit, or a mixture of chicken and rabbit blood and their gut microbiota characterized using 16S rRNA gene amplification and MiSeq sequencing. The gut bacterial communities of mosquitoes fed on the three blood meal treatments clustered separately, suggesting that host species identity and mixed blood feeding are key determinants of gut bacterial community composition in mosquitoes. Mixed blood meal had a synergistic effect on both OTU richness and Shannon diversity index suggesting that mixed blood feeding can offset the nutritional deficit of blood meals from certain host species. The microbial communities observed in this study were distinct from those identified from similarly fed Ae. aegypti from our previous study. These findings demonstrate that vector host-feeding preferences can influence gut microbial composition and diversity which could potentially impact pathogen acquisition and transmission by the vector. The results also demonstrate that different microenvironmental conditions within the laboratory may play an important role in structuring the microbial communities of independently reared mosquito colonies.