Evaluation of the effectiveness of Interceptor bed net on controlling disease vectors Aedes aegypti in Vietnam, 2007

ABSTRACT

Background: Using insecticides is considered as a temporary and rapid method for interrupting the disease transmission through disease vectors such as dengue. The insecticide Fendona, when absorbed into bed nets, is slowly released and rapidly knocks out, kills or repels mosquitoes as they come into contact with the bed net. Objectives: To evaluate the effectiveness of the Interceptor bed net (a unique textile-finishing product developed by BASF, Singapore PTE. LTD, that were coated with the Fendona insecticide) on controlling disease vector Aedes aegypti. Subjects and method: An experimental trial was carried out at the National Institute of Hygiene and Epidemiology and in the field of Hien Giang commune, Thuong Tin district, Ha Tay province. The changes of efficacy of Interceptor bed net were compared by not washing with washing at the different levels. Results: The unwashed bed nets can knock out and kill Aedes aegypti mosquitoes by 50% after 20 minutes of exposure on every trial. About 90-100% of total mosquitoes were killed after the first 30 minutes of exposure. Bed net\u2019s efficacy remains until 24 hours of the trial. The recovery rate of the mosquito is 0%. The same results were also observed after 90 days, 36 days and 18 days of bed nets being laundered. However, after 9 day of washing, the bed nets can only kill the mosquitoes up to about 90-95% of the total after the first 30 minutes of exposure. It also reached 100% of killing after 24 hours. However, its efficacy was conversely reduced with regard to the increase of laundry times. Conclusion: The density of adult mosquitoes and larvae for Aedes aegypti was significantly reduced in the intervention areas, even at zero level in comparison to the control sites. The insecticide had no side-effect or any stimulation to users, community, poultry, cattle and environment in the intervention sites.