September 17, 2007: The U.S. Army and Marines are beginning to use field uniforms that are treated with insect (mainly mosquitos) repellant (permethrin) during manufacture. This means the uniforms never have to be treated again. Currently, troops have permethrin either sprayed on (and last for about six washes), or soak uniforms in it (and last for 50 washes). The factory level treatment tends to eliminate complaints that the sprayed or soaked approach makes the uniforms stuffy (they don't "breathe.") Some troops complain of rashes from the permethrin, but there's no medical evidence of that. There are also unfounded rumors that permethrin causes cancer. What permethrin does do is keep mosquitoes away, and in areas where the insects transmit lots of diseases (like malaria), that is a big deal. Tests have shown that troops who just rub a mosquito repellant (like Deet) on their skin, still get bitten about ten times an hour. But with Deet and permethrin treated uniforms, you'll get bitten maybe once or twice a day. When permethrin treated uniforms are used, cases of mosquito borne diseases go down over 80 percent.