Blood Feeding Status, Gonotrophic Cycle and Survivorship of Aedes (Stegomyia) aegypti (L.) (Diptera: Culicidae) Caught in Churches from Merida, Yucatan, Mexico

Abstract

Blood-feeding status, gonotrophic cycle, and survival rates of Aedes (Stegmyia) aegypti (L.) was investigated in catholic churches from Merida, Yucatan. Female Ae. aegypti were caught using backpack aspirator during 25 consecutive days in rainy (2015) and dry season (2016). Blood-feeding status was determined by external examination of the abdomen and classified as unfed, fed, and gravid. Daily changes in the parous-nulliparous ratio were recorded, and the gonotrophic cycle length was estimated by a time series analysis. Also, was observed the vitellogenesis to monitoring egg maturity. In total, 408 females Ae. aegypti were caught, and there was a significant difference in the number of females collected per season (Z = -6.729, P ≤ 0.05). A great number was caught in the rainy season (n = 329). In the dry season, 79 females were caught, which the fed females were twice greatest than the unfed. The length of gonotrophic cycle was estimated on the base of a high correlation coefficient value appearing every 4 days in rainy at 26.7 ± 1.22°C, and 3 days in dry season at 29.8 ± 1.47°C. The daily survival rate of the Ae. aegypti population was higher in both seasons, 0.94 and 0.93 for the rainy and dry season, respectively. The minimum time estimated for developing mature eggs after blood feeding was similar in both seasons (3.5 days in rainy versus 3.25 days in dry). The measurement of the vectorial capacity of Ae. aegypti in catholic churches could help to understand the dynamics of transmission of arboviruses in sites with high human aggregation.

Study of Aedes aegypti population with emphasis on the gonotrophic cycle length and identification of arboviruses: implications for vector management in cemeteries

“…aegypti . In houses, Rebollar-Tellez et al 6 estimated a seven-day cycle, while in churches, the duration of the gonotrophic cycle was similar to the one found in the present study of three and four days during the dry and rainy season, respectively 10 .…”

“…In churches, 47% of the Ae. aegypti females were collected as fed, 34% as unfed and 19% as gravid females 10 .…”

“…During the rainy season, the mean rainfall is 1,000 mm and the mean temperature of 27.5 °C. During the dry season, the mean rainfall is 300 mm and the mean temperature is 25.1 °C 10 .…”

“…The blood feeding status (Sella’s stages) was determined by external examination of the abdomen. Insects were then grouped as unfed (the collapsed abdomen and the ovaries occupy one-third of the abdomen), fed (freshly fed, bright red blood and the ovaries occupy two to three segments ventrally; the sub-gravid with dark blood and with great space reduced and ovaries occupy most of abdomen) and gravid (blood completely digested or present only as a black trace or line) 10 .…”

“…Previous studies reported engorged Ae. aegypti in schools and churches 10 , 11 . Therefore, the vectorial capacity of mosquitoes must be evaluated in cemeteries because they have breeding sites and are near the houses.…”