Determinants of Aedes mosquito density as an indicator of arbovirus transmission risk in three sites affected by co-circulation of globally spreading arboviruses in Colombia, Ecuador and Argentina

TALBOT BENOIT; SANDER, BEATE; GONZALEZ ROSAS, CAMILA; CEVALLOS, VARSOVIA E.; BENÍTEZ, DENISSE; ET AL; MIRETTI MARCOS; KULKARNI, MANISHA

PARASITES AND VECTORS

BIOMED CENTRAL LTD

Lugar: Londres; Año: 2021

1756-3305

BackgroundThe global impact of Zika virus in Latin America and the Caribbean has drawn renewed attention tocirculating mosquito-borne viruses in this region, such as dengue and chikungunya. Our objective was toassess socio-ecological factors associated with Aedes mosquito vector density as a measure of arboviraltransmission risk in three cities of potential recent Zika virus introduction: Ibagué, Colombia; Manta,Ecuador; and Posadas, Argentina, in order to inform disease mitigation strategies.MethodsWe monitored Aedes mosquito populations over 12 months starting in 2018 in a total of 1,086 randomlyselected households, using indoor and peridomestic mosquito collection methods. For each sampledhousehold, we collected socio-economic data using structured questionnaires and data onmicroenvironmental conditions using iButton data loggers.ResultsA total of 3,230 female Aedes mosquitoes were collected, of which 99.8% were Ae. aegypti and 0.2% wereAe. albopictus. Mean female Aedes spp. mosquito abundance per household was 1.71. We modeled theinteraction between neighborhood and household wealth pro􀂦les, and found signi􀂦cantly lower Aedesdensity in highest compared to lowest and middle wealth households, although the effect differed bylevel of neighborhood wealth. We used mixed-effects Poisson regression analyses to identify predictorsof Aedes density, using month, neighborhood, and country as random-effect variables. Across study sites,the number of household occupants (Incidence rate ratio, IRR = 1.08), presence of entry points formosquitoes into the household (IRR = 1.51), and presence of decorative vegetation (IRR = 1.52) wereassociated with higher Aedes density; while being in the highest wealth tertile of household wealth (IRR =0.78), knowledge of how arboviruses are transmitted (IRR = 0.94) and regular emptying of watercontainers by occupants (IRR = 0.79) were associated with lower Aedes density.ConclusionsOur study addresses the complexities of arbovirus vectors of global signi􀂦cance at the interface betweensociety and the environment. Our results point to several determinants of Aedes mosquito vector densityin countries with co-circulation of multiple Aedes-borne viruses, and could help us identify targets ofpractical intervention for disease prevention and control.