Success Story

Products To Protect Consumers and the Military From Insects

Products To Protect Consumers and the Military From Insects

During World War II, the USDA and military formed a team to develop methods for stopping transmission of insect-borne diseases. It was there that DDT-which had been discovered in Switzerland years before but never used-was demonstrated to kill lice that transmit epidemic typhus and fleas that transmit plague. Using this knowledge, USDA and military entomologists came up with a system for mass delousing that led to saving thousands of U.S. troops from deadly typhus-and ultimately about 25 million people worldwide. In addition, the World Health Organization estimated that widespread use of DDT prevented more than 25 million deaths from malaria following World War II.

The USDA military collaboration also resulted in the use of n-n-diethylnetatoluamide (DEET) as an insect repellent. USDA scientists in Orlando, Florida, and Beltsville, Maryland tried keeping pests away with literally thousands of substances, reporting their findings to chemists. Chemists observed that one particular group of chemicals had repellent action. In time, they came up with 33 new chemicals and sent them to the military for testing. One of the chemicals, DEET, proved superior to all others. Beginning in 1946, the military began using DEET as topical insect repellent. USDA registered DEET for public use and in 1957 it was marketed as 6-12 for civilian use.

Today, DEET remains the most effective mosquito repellent available. World Health Organization statistics report that mosquitoes spread about 4 million malaria cases, causing about 1 million deaths globally each year. These insects also spread dengue-fever-related illnesses, which lead to 24,000 deaths annually.

More recently, the spread in the United States of West Nile virus, also mosquito-borne, has focused new attention on DEET. The Centers for Disease Control and Prevention recommend that people in affected areas always wear an insect repellent containing DEET when they go outside during mosquito season as the best protection against being exposed to West Nile virus

Some possible concerns about DEET posing a health risk have been raised. EPA has reviewed the data and determined “normal use of DEET does not present a health concern.” Several changes have been made in the label directions to ensure DEET is safely applied, mainly to avoid oversaturating skin or clothing and not to spray infants

It is impossible to calculate how much illness, death, and misery has been prevented during the last 50 years by simple application of a bit of DEET.