Density and diversity of Culicidae (Diptera), with analysis of viral circulation, in urban public establishments in Northern Paraná, Brazil

Brazil has been suffering a dengue (DENV) epidemic in 2019 and 2022 and records cases of Zika (ZIKV) and chikungunya (CHIKV). Londrina city, Paraná, stands out for the number of cases and deaths from dengue. Therefore, this study aimed to verify the density and diversity of mosquitoes present in urban public establishments of Londrina, to analyze their ecological relationships, and to investigate the presence of the DENV, ZIKV, and CHIKV. Ovitraps were installed in outdoor sites in two public establishments in each region of Londrina, while adult culicids were caught indoors with a Nasci aspirator. A total of 5077 eggs were obtained in 77 ovitraps. The South region had the highest infestation while the East had the lowest (Ovitrap Positivity Index: 38% and 25%; Egg Density Index: 67.83 and 19.03, respectively). From eggs, 704 Aedes aegypti females and 71 Aedes albopictus females were obtained, while in the aspiration of adults, 99 A. aegypti and 11 Culex quinquefasciatus were captured, the highest number in the West and the lowest in the North. The DENV-II virus was detected in a pool of 17 A. aegypti females in the West region. The results demonstrate high density of pathogen vector species, mainly A. aegypti, in and around establishments, alerting to the need for constant local entomological surveillance to prevent viral circulation, mainly in crowded places. The presence of A. albopictus around the establishments also alerts to the urbanization of the species and potential participation in the viral circulation, demonstrating the need for constant monitoring.

Keywords:
Mosquitoes; Urbanization; Ecology; Viral investigation