New study alters old protocol of washing first
A tick navigates a sweater. Scientists are revising tick-cleaning recommendations.
By Ann Lukits in the Wall Street Journal
May 30, 2016 3:03 p.m. ET
There is a better way to kill ticks on your clothes than the method often recommended currently, new research suggests. The study, published online in the journal Ticks and Tick-borne Diseases, says just six minutes spinning dry clothes in a hot dryer should kill all the ticks and reduce the risk of tick-related illnesses.
The Centers for Disease Control and Prevention currently recommends washing tick-infested clothes and then drying them for one hour.
The recent research found that drying time can be significantly reduced if clothes aren’t washed first, as ticks are extremely sensitive to dryness.
Drying should be combined with other prevention methods, such as the use of repellent, the study said. Tick bites are responsible for an estimated 300,000 Lyme-disease infections in the U.S. a year, and several other diseases, according to the study, conducted by the CDC’s National Center for Emerging and Zoonotic Infectious Diseases in Colorado.
The researchers washed and dried hundreds of lab-raised blacklegged ticks (Ixodes scapularis) and immature nymphs, five at a time, in cloth bags in residential washers and dryers in Vermont, Maine and Massachusetts. Ticks and nymphs that survived washing were dried with wet towels at low and high heat. Control ticks were placed in containers at room temperature. In separate experiments, bugs were dried—without pre-washing—with dry towels at various temperatures.
The bugs survived cold-water washes, 94% survived warm-water washes, and 50% survived hot-water washes. Ticks that survived washing took 70 minutes to kill in dryers on low heat and 50 minutes at high heat. All control ticks survived for 24 hours.
By comparison, all ticks and nymphs dried with dry towels were killed in four to 11 minutes, depending on the temperature.
The researchers did include a caveat. The cloth bags that the ticks were washed and dried in may have protected the ticks from heat and dryness.