<i>Aedes</i> Mosquito Distribution along a Transect from Rural to Urban Settings in Yaoundé, Cameroon

• Main Authors: Borel Djiappi-Tchamen, Mariette Stella Nana-Ndjangwo, Timoléon Tchuinkam, Idene Makoudjou, Elysée Nchoutpouen, Edmond Kopya, Abdou Talipouo, Roland Bamou, Marie Paul Audrey Mayi, Parfait Awono-Ambene, Charles Wondji, Christophe Antonio-Nkondjio
• Format: Article
• Language: English
• Published: MDPI AG 2021-09-01
• Series: Insects
• Subjects: <i>Aedes albopictus</i>; <i>Aedes aegypti</i>; rural; peri-urban; urban; breeding site
• Online Access: https://www.mdpi.com/2075-4450/12/9/819

Introduction: The surveillance of mosquito vectors is important for the control of arboviruses diseases worldwide. Detailed information on the bionomics and distribution of their main vectors, <i>Aedes aegypti</i> and <i>Aedes albopictus,</i> is essential for assessing disease transmission risk and for better planning of control interventions. Methods: Entomological surveys were carried out from November 2019 to November 2020 in six localities of Yaoundé city following a transect from urban to rural settings: two urban (Obili, Mvan), two peri-urban (Simbock, Ahala) and two rural areas (Lendom, Elig-essomballa)—during rainy and dry seasons. All water containers were inspected. <i>Aedes</i> mosquito abundance, species distribution and seasonal distribution patterns were compared using generalized linear models. Stegomyia indexes were estimated to determine the risk of arbovirus transmission. Results: A total of 6332 mosquitoes larvae were collected (2342 in urban areas, 1694 in peri-urban areas and 2296 in rural sites). <i>Aedes</i> species recorded included <i>Ae. albopictus</i>, <i>Ae. aegytpi</i>, <i>Ae. simpsoni and Aedes</i> spp. High mosquito abundance was registered in the rainy season (4706) compared to the dry season (1626) (<i>p</i> < 0.0001). <i>Ae. albopictus</i> was the most abundant <i>Aedes</i> species in urban (96.89%) and peri-urban (95.09%) sites whereas <i>Ae. aegypti</i> was more prevalent in rural sites (68.56%) (<i>p</i> < 0.0001). Both species were found together in 71 larval habitats. <i>Ae. albopictus</i> was mostly found in discarded tires (42.51%), whereas <i>Ae. aegypti</i> was more prevalent in plastic containers used for storing water (65.87%). The majority of <i>Aedes</i> mosquitoes’ breeding places were situated close to human dwellings (0–10 m). Conclusion: Uncontrolled urbanization seems to greatly favour the presence of <i>Aedes</i> mosquito species around human dwellings in Yaoundé. Controlling <i>Aedes</i> mosquito distribution is becoming urgent to reduce the risk of arbovirus outbreaks in the city of Yaoundé.