For over 75 years, USDA scientists have been developing ways to protect the U.S. military around the world from powerful adversaries—mosquitoes and other biting arthropods that cause disease. Their work began in 1942 in a small USDA field laboratory in Orlando, where scientists made key discoveries about new chemicals for controlling these pests. At the time, the most effective repellents lasted only 2 hours, and the U.S. military needed a repellent that could protect for 10 hours.