Pilot studies of abate as a larvicide for control of Aedes aegypti in Bangkok, Thailand.

Autor(es): Bang Y H; Tonn R J; Jatanasen S

Resumo: Difenphos (Abate) sand granules were used against Aedes aegypti in a control project area of 614 houses inhabited by 4100 persons in Bangkok (illustrated by an air photograph). The area was divided into 2 approximately equal parts for 2 different control procedures. The first method included treatment of all larval habitats, with mass retreatment when 1% of the total water jars had become positive. The second method comprised one mass treatment, followed by retreatment of individual containers as they became positive. The first method required 3 times as much larvicide, whereas the second needed 3 times as much labour in man-hours. Water jars and ant traps were the most common larval habitats. All of them were treated with 1 % difenphos sand granules at a target dosage of 1 p.p.m. and were examined every 2 weeks. The adult collections, using human bait, were done weekly at 12 permanent stations. Other adult collections were conducted to determine the population level, including both biting and resting mosquitoes. Ovitraps were set up weekly inside houses selected in both treatment areas. The rate of re-infestation of the treated jars did not significantly differ in their type, size, location, water usage practice, presence of organic debris or direct sun exposure. The reduction of adult mosquitoes in the two treated areas was about equal, i.e. approximately 85% after 10 days of treatment. The results of adult collections indicated both the efficacy of treatment and seasonal variation. The adult density increased in the wet season and decreased in the cool and hot dry seasons. The ovitrap method did not show quantitative adult density, but merely indicated the presence of females. Y. Rongsriyam.

Imprenta: The Southeast Asian Journal of Tropical Medicine and Public Health, v. 3, n. 1, p. 106-115, 1972

Descritores: Aedes aegypti - Pathogenesis ; Aedes aegypti - Viral infections ; Aedes aegypti - Larvicide ; Aedes aegypti - Public health

Data de publicação: 1972