Building the vector in? Construction practices contribute to the invasion and persistence of Anopheles stephensi in Jigjiga, Ethiopia

Yared, S.; Gebresilassie, A.; Aklilu, E.; Abdulahi, E.; Kirstein, O. D.; Gonzalez-Olvera, G.; Che-Mendoza, A.; Bibiano-Marin, W.; Waymire, E.; Lines, J.; Lenhart, A.; Kitron, U.; Carter, T.; Manrique-Saide, P.; Vazquez-Prokopec, G.

doi:10.1101/2023.05.23.541906

bioRxiv · 10.1101/2023.05.23.541906

Building the vector in? Construction practices contribute to the invasion and persistence of Anopheles stephensi in Jigjiga, Ethiopia

Yared, S.·Gebresilassie, A.·Aklilu, E.·Abdulahi, E.·Kirstein, O. D.·Gonzalez-Olvera, G.·Che-Mendoza, A.·Bibiano-Marin, W.·Waymire, E.·Lines, J.·Lenhart, A.·Kitron, U.·Carter, T.·Manrique-Saide, P.·Vazquez-Prokopec, G.

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Abstract

Anopheles stephensi is a major vector of malaria in Asia and the Arabian Peninsula, and its recent invasion into Africa poses a significant threat to malaria control and elimination efforts on the continent. The mosquito is well-adapted to urban environments, and its presence in Africa could potentially lead to an increase in malaria transmission in cities. Most of the knowledge about An. stephensi ecology in Africa has been generated from studies conducted during the rainy season, when vectors are most abundant. Here, we provide evidence from the peak of the dry season in the city of Jigjiga, Ethiopia, and report the finding of An. stephensi immature stages infesting predominantly water reservoirs made to support construction operations (in construction sites or associated with brick manufacturing businesses). Political and economic changes in Ethiopia (and particularly the Somali Region) have fueled an unprecedented construction boom since 2018 that, in our opinion, has been instrumental in the establishment, persistence and propagation of An. stephensi via the year-round availability of perennial larval habitats associated with construction. We argue that larval source management during the dry season may provide a unique opportunity for focused control of An. stephensi in Jigjiga and similar areas.

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Yared, S., Gebresilassie, A., Aklilu, E., Abdulahi, E., Kirstein, O. D., Gonzalez-Olvera, G., Che-Mendoza, A., Bibiano-Marin, W., Waymire, E., Lines, J., Lenhart, A., Kitron, U., Carter, T., Manrique-Saide, P., Vazquez-Prokopec, G.. 2023-05-24. Building the vector in? Construction practices contribute to the invasion and persistence of Anopheles stephensi in Jigjiga, Ethiopia. https://doi.org/10.1101/2023.05.23.541906

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