Entomological investigation after an outbreak of dengue at the riverside of Rio Doce, Espírito Santo State, Brazil

• Published in: Transactions of the Royal Society of Tropical Medicine and Hygiene 2024-12
• Main Authors: Rezende, Helder Ricas, Vicente, Creuza Rachel, Chahad-Ehlers, Samira, Cardoso, Orlei Amaral, Cerutti, Jr, Crispim, Romano, Camila Malta, de Souza, Caio Santos, Caleiro, Giovana Santos, Guedes, Bruno Luiz Miranda, Ferreira, Lucas Mendes, de Alencar, Filomena Euridice Carvalho
• Format: Article
• Language: English
• ISSN: 1878-3503; 1878-3503
• DOI: 10.1093/trstmh/trae123

In 2019, a dengue outbreak involving Aedes albopictus occurred in a rural area of Espírito Santo, Brazil, motivating our study in Sooretama and Linhares. We set traps to sample immature mosquito larvae at 40 sites, with weekly inspections from July 2022 to January 2023. Adult specimens were collected monthly at 19 sites, each collection lasting 15 min. The collections were performed during daylight using a Castro vacuum device, a small electric vacuum suction device, a net capture device and insect cages. We conducted molecular analyses of adult Aedes to identify arbovirus infection. Among 20 217 immature forms, we identified Aedes aegypti (n=16 340), Aedes albopictus (n=3403), Culex quinquefasciatus (n=426) and Limatus durhami Theobald 1901 (n=48). Of the 3026 adult specimens, there were C. quinquefasciatus (n=2857), A. aegypti (n=141) and A. albopictus (n=28). Each site had an average of 159 adult specimens, 16 per house. Among the 159 specimens, 150 were C. quinquefasciatus. The average frequency of adult A. aegypti per house was 1.2 (0.08 per minute of collection). Adult Aedes were not infected. Entomological surveillance should consider A. albopictus and A. aegypti in rural areas, providing proper vector control strategies to prevent the spread of arboviruses.