2011 Annual Report 1a.Objectives (from AD-416) Evaluate the ability of insecticide-treated materials to kill mosquitoes indoors over extended periods of time. 1b.Approach (from AD-416) Insecticide-treated wall linings will be placed on the inner walls of small, wooden huts. Bioassay tests will be conducted in these huts with three genera of laboratory-reared mosquitoes on a weekly basis. Some wall linings will be subjected to simulated weathering conditions before being tested. 3.Progress Report This project is related to Objective 2 of the in-house project - Develop new application methods for pesticides to biting Nematocera that minimize environmental exposure and that optimize lethal or repellent effect, including presentation on clothing, aerosol application in or outdoors, residual application, disinsection of aircraft, and delivery of spatially repellent compounds. The World Health Organization cone bioassay touch test was used to evaluate mosquito knockdown and mortality caused by the insecticide-treated durable wall lining against 3 mosquito species. A second test method, which utilized 100 free-flying female mosquitoes of each species, was also used. During the first 9 months of the study, 100% mortality was observed with the cone test and there was approximately 90 percent mortality among the free-flying mosquitoes released in the huts. Both of these results reflected the capability of the treated wall lining to kill mosquitoes over a 9-month period. Since this project began, ARS staff met with Vestergaard-Frandsen personnel to review these results and discuss ongoing research at the Annual Meeting of the American Society of Tropical Medicine and Hygiene in Atlanta, GA and at the ARS Center for Medical, Agricultural and Veterinary Entomology in Gainesville, FL. Progress was monitored through meetings, telephone calls, and e-mails.