The importance of entomo-virological investigation of Yellow Fever Virus to strengthen surveillance in Brazil

Brazilian National Council for Scientific and Technological Development (CNPq), grant numbers 314522/2021-2 to A.C.R.C., 166720/2017-8 and 106256/2018-1, to L.H.A.H, and 310295/2021-1, to P.F.d.C.V. Funding was also provided by National Institute of Science and Technology for Emerging and Reemerging Viruses in partnership with CNPq, grant number 406360/2022-7, to P.F.d.C.V.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Pará State University. Center for Biological and Health Sciences. Belém, PA, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Pará State University. Center for Biological and Health Sciences. Belém, PA, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Pará State University. Center for Biological and Health Sciences. Belém, PA, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Pará State University. Center for Biological and Health Sciences. Belém, PA, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil / Federal University of Pará. Institute of Biological Sciences. Belém, PA, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Goiás Public Health Laboratory. Goiânia, GO, Brazil.Goiás Public Health Laboratory. Goiânia, GO, Brazil.Ministry of Health. Health and Environment Surveillance Secretariat. Brasília, DF, Brazil.World Health Organization. Pan American Health Organization. Public Health Emergency Department. Brasília, DF, Brazil.Oswaldo Cruz Foundation. René Rachou Institute. Belo Horizonte, MG, Brazil.Oswaldo Cruz Foundation. René Rachou Institute. Belo Horizonte, MG, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde e Ambiente. Instituto Evandro Chagas. Ananindeua, PA, Brasil.The largest outbreak of sylvatic yellow fever virus (YFV) in eight decades was recorded in Brazil between 2016–2018. Besides human and NHP surveillance, the entomo-virological approach is considered as a complementary tool. For this study, a total of 2904 mosquitoes of the Aedes, Haemagogus and Sabethes genera were collected from six Brazilian states (Bahia, Goiás, Mato Grosso, Minas Gerais, Pará, and Tocantins) and grouped into 246 pools, which were tested for YFV using RT-qPCR. We detected 20 positive pools from Minas Gerais, 5 from Goiás, and 1 from Bahia, including 12 of Hg. janthinomys and 5 of Ae. albopictus. This is the first description of natural YFV infection in this species and warns of the likelihood of urban YFV re-emergence with Ae. albopictus as a potential bridge vector. Three YFV sequences from Hg. janthinomys from Goiás and one from Minas Gerais, as well as one from Ae. albopictus from Minas Gerais were clustered within the 2016–2018 outbreak clade, indicating YFV spread from Midwest and its infection in a main and likely novel bridging vector species. Entomo-virological surveillance is critical for YFV monitoring in Brazil, which could highlight the need to strengthen YFV surveillance, vaccination coverage, and vector control measures