Pilot Study Assessing the Effectiveness of Long-Lasting Permethrin-Impregnated Clothing for the Prevention of Tick Bites

Abstract

Introduction: Tick-borne diseases such as Lyme disease, Rocky Mountain spotted fever, and ehrlichiosis are a significant concern for many thousands of workers who have frequent and unavoidable exposure to tick-infested habitats. Many North Carolina state employees with outdoor occupations report multiple tick bites each year, indicating that existing tick preventive strategies may be underutilized or ineffective. Treatment of clothing with permethrin, a nontoxic chemical with insecticidal, knockdown, and repellent properties, is highly effective against ticks. However, most permethrin products must be reapplied after several washings to maintain insecticidal activity. Recently, a factory-based method for long-lasting permethrin impregnation of clothing has been developed by Insect Shield, Inc., that allows clothing to retain insecticidal activity for over 70 washes. Methods:A nonrandomized open label pilot study was conducted to determine the effectiveness of Insect Shield-treated clothing for the prevention of tick bites among 16 outdoor workers from the North Carolina Division of Water Quality under actual field conditions. Participants completed questionnaires at the start of follow-up (March, 2008) and at the end of follow-up (September, 2008), and tick bites and outdoor work hours were reported on weekly tick bite logs for the entire follow-up period. Results: Subjects wearing Insect Shield-treated clothing had a 93% reduction ( p < 0.0001) in the total incidence of tick bites compared to subjects using standard tick bite prevention measures. Conclusion: This study provides preliminary evidence that long-lasting permethrin-impregnated clothing may be highly effective against tick bites.

Long-Lasting Permethrin-Impregnated Clothing Protects Against Mosquito Bites in Outdoor Workers

“…LLPI clothing is efficacious against other arthropod vectors, such as ticks and chiggers, as has been demonstrated in two U.S. studies 17,18 and in a recent German study. 6 Work by WilderSmith and others indicate that LLPI clothing would be a costeffective and acceptable means of preventing dengue.…”

“…We first conducted an open-labeled study of 16 North Carolina Division of Water Quality worker subjects, and found a 94% protective efficacy over a 1-year period. 17 We then conducted an RCT with 159 North Carolina parks and forestry rangers; the protective efficacy was 83% in the first year, but only 36% in the second year. 18 This study suggests that treated clothing had lost its efficacy over a period of 1 year.…”

Compendium of Veterinary Standard Precautions for Zoonotic Disease Prevention in Veterinary Personnel: National Association of State Public Health Veterinarians: Veterinary Infection Control Committee 2015

“…168,169 Regardless of the geographic location of the field work, permethrintreated clothing has been demonstrated to be highly effective at reducing tick bites and would be recommended for those veterinarians and assistants with occupational exposures. 170 Animals may act as mechanical carriers for ticks, and it is important to check patients as they enter a clinic to limit introduction of arthropod vectors into the indoor work environment. 171 Integrated pest management is the recommended approach to the control of rodents and vectors in veterinary medical buildings.…”

Data collection for risk assessments on animal health (Acronym: DACRAH) : Final Report

“…The European Food Safety Authority reserves its rights, view and position as regards the issues addressed and the conclusions reached in the present document, without prejudice to the rights of the authors. (Vaughn and Meshnick, 2011) Impregnated clothing Efficacy of 0.93 recorded 180 days after application.…”