Os impactos de diferentes temperaturas na sobrevivência e reprodução do mosquito Aedes aegypti

Abstract

The mosquito Aedes aegypti is the primary vector for arboviruses such as dengue, chikungunya, and Zika. It is known that climatic variables affect the dynamics of the vector, potentially contributing to its population increase and, consequently, to the rise in disease transmission. This study aimed to analyze the influence of temperature on the development time of Aedes aegypti mosquitoes. Eggs of Aedes aegypti from the Lapavet-SD strain, obtained from the colony of the Laboratory of Biotechnology Applied to Parasites and Vectors at CBiotec-UFPB, were used. These were kept in a BOD incubator under controlled conditions of 28 ± 2°C, relative humidity of 75 ± 5%, and a 12-hour light/dark photoperiod. For the tests, 180 eggs were subdivided into six groups: two exposed to a temperature of 20 ± 2°C, two to 28 ± 2°C, and the remaining to 36 ± 2°C. The development time from the egg stage to the death of the last mosquito was determined through survival analysis using the Log-rank (Mantel Cox) method, and nitric oxide (NO) production was measured using the Griess method. The results showed significant differences in the development curves and survival of Aedes aegypti mosquitoes. At 28°C (control group), the average duration of the larval stage was 7 days, while at 20°C it was 11 days, and at 36°C, the larval stage lasted 3 days. Additionally, the average duration of the pupal stage was 3 days in the control group (28°C), 7 days at 20°C, and 11 days at 36°C. The adult stage duration for mosquitoes exposed to 28°C was 27 days. Mosquitoes raised at 20°C lived for 152 days, while those at 36°C survived for 19 days. Furthermore, nitric oxide production was similar between the control group (28°C) and the group maintained at 20°C. However, the group maintained at 36°C showed significantly higher nitric oxide levels compared to the other study groups. A higher quantity of prohemocytes was observed compared to other types of cells present in the hemolymph. These results contribute to the understanding of the relationship between temperature and the development of Aedes aegypti mosquitoes, thereby predicting potential changes in their distribution patterns in relation to climate changes.