Assessing Urban Yellow Fever Transmission Risk: Aedes aegypti Vector Competence in Argentina

BOAGLIO, ESTEFANÍA R.; MUTTIS, EVANGELINA; FEROCI, MARIEL; FABBRI, CINTIA; MINARDI, GRACIELA; SÁNCHEZ, JULIANA; MICIELI, MARÍA V.; GOENAGA, SILVINA

Viruses

MDPI

Año: 2025 vol. 17

Yellow fever is a viral disease with historical importance since epidemics causedthousands of deaths at the end of the 19th century in Argentina. That event was associatedwith the presence of Aedes aegypti. After the mosquito eradication in South America in the1960–1970 decade, no epidemic was detected related to this species but epizootics haveoccurred due to sylvatic vectors belonging to Haemagogus and Sabethes genera. Due to therecolonization of Ae. aegypti and its expanded distribution, the risk of the urbanizationof yellow fever has increased over time. However, the reasons why the urban cycle ofthe yellow fever virus (YFV) has not occurred in South America so far are unknown.We explore the vector competence of Ae. aegypti for YFV transmission. The mosquitosevaluated belonged to colonies from center and northwest cities from Argentina, takinginto account the particular genetic features of this mosquito species detected in this countryfrom 2016. We used a viral strain originally isolated in 2009 from Sabethes albiprivus in thecountry. Viral infection in mosquito body, legs, and saliva was evaluated to estimate therates of infection, dissemination, and transmission. Our results indicate that both mosquitocolonies are competent vectors in the transmission of the YFV but with differences betweenthem. Regarding the infection timeline, we observed a very early infection in the La Platacolony at 3 DPI in contrast to previous studies. This research improves our understandingof the risks of urban YFV transmission in Argentina, highlighting the need for surveillanceand specialized vector control strategies in urban settings to prevent yellow fever outbreaks.