Assuring that uniforms issued to U.S. military personnel are properly treated to repel mosquitoes is now possible, thanks to a new testing method developed by an Agricultural Research Service (ARS) scientist.
Since 1991, treatment of military uniforms with the insecticide permethrin has been available to help protect troops from mosquitoes that transmit human disease pathogens. This method is a valuable addition to the protection provided by insect repellents, but it is a challenge to be sure that the many kinds of fabrics and uniforms are adequately treated.
To assist the military with this problem, chemist Ulrich Bernier at the ARS Mosquito and Fly Research Unit, part of the Center for Medical, Agricultural and Veterinary Entomology in Gainesville, Fla., developed a new insect bite protection efficacy assessment that has been adopted by the United States Marine Corps (USMC).
His new methodology requires assessment of multiple uniform fabric specimens on four human volunteers and against two species of mosquitoes before the uniforms are accepted for production and distribution to military personnel. The precise results gained from this method provide the military with information on how well the uniform will protect and prevent deployed personnel from receiving insect bites.
This methodology is currently applicable only to the military and is used to ascertain each uniform manufacturer's ability to provide uniforms that will protect troops from mosquito bites.
To prevent mosquito bites, uniforms must be properly treated with permethrin. Otherwise, the repellent action will be lost when the uniforms are washed. The USMC found that newly introduced permanent press uniforms were not retaining effective amounts of permethrin. To solve this problem, the USMC focused on ways to improve permethrin retention by changing the treatment process and the type of chemical binders used.
Bernier's methodology was necessary because there was no manufacturing standard by which to evaluate mosquito protection afforded by the uniforms.
ARS is a scientific research agency in the U.S. Department of Agriculture.