Jeomhee Mun, a UC Berkeley research specialist in insect biology, is another co-author of the paper.
Lane and Steinlein conducted the experiments on two back-to-back days in three consecutive weeks in 2002 between late May and mid-June. Decked out in white clothing from top to bottom, with pant legs tucked into white socks and seams sealed with duct tape, the researchers set out to learn how people might acquire nymphal ticks.
"If we're going to develop effective strategies and educational programs for the prevention of Lyme disease, it is critical that we understand how people are exposed to the ticks that transmit the bacteria in the first place," said Lane. "We intentionally looked at behaviors that people would typically engage in while spending time in the woods."
The researchers sat on logs, sat against trees, gathered wood, walked through leaves, sat still on leaf litter and sat and stirred up leaf litter for set amounts of time. Lane noted that turkey hunters can easily spend up to an hour or longer sitting with their backs against trees while trying to call in toms during the spring hunting season.
After each activity, in scenes strikingly reminiscent of primate grooming behavior, the researchers meticulously picked off and counted the ticks on their clothing and bodies. They also used an adhesive lint roller to pick up ticks that might otherwise have escaped their attention. All told, they found a total of 86 nymphal ticks on their bodies during the field trials.
"Activities that were riskiest involved considerable contact with wood," said Steinlein. "Of the six behaviors we analyzed, sitting still on leaf litter was the least riskiest behavior, resulting in tick exposure only eight percent of the time."
Why the difference between wood products and leaf litter? The clue may be in an important animal host for
Contact: Sarah Yang
University of California - Berkeley