The US military was apparently on to something when it began treating soldiers' uniforms with permethrin in the 1980s. The move was based on tests showing the EPA-registered pesticide, which mimics extracts from the chrysanthemum flower, prevented tick and other insect bites. Three decades later, it still holds up to scrutiny, according to CDC researchers. They let black-legged, lone star, and American dog ticks loose on 10 types of permethrin-treated clothing and saw speedy effects, as described in a recent issue of the Journal of Medical Entomology. Juvenile black-legged ticks died in less than a minute, while others started "rolling" away, researcher Lars Eisen tells NPR. Per American Veterinarian, all ticks saw "loss of normal movement," meaning they were unable to bite, when left in contact with the clothing for up to five minutes.
Though some seem concerned about the safety of permethrin-treated clothing, the EPA says it is "unlikely to pose any significant immediate or long-term hazard to people wearing it." Getting the pesticide on your skin results in only minor irritation, per the National Pesticide Information Center. In a Wired article headlined, "We Have No Idea How Bad the US Tick Problem Is," Megan Molteni argues that "protective clothing, repellants, and daily partner tick-checks" are "better than nothing" at preventing the spread of tick-borne illnesses like Lyme disease and Rocky Mountain spotted fever. "But with more and more people getting sick, the US will need better solutions soon," Molteni writes, pointing to a nationwide tick surveillance program being organized by the CDC. The agency says tick-borne disease cases doubled in the US from 2004 to 2016. (A mom's natural tick spray is undergoing tests.)