title: Pilot study assessing the effectiveness of factory-treated, long-lasting permethrin-impregnated clothing for the prevention of tick bites during occupational tick exposure in highly infested military training areas, Germany.
abstract: The protective effectiveness of factory-based permethrin-impregnated polymer-coated battle dress uniforms (PTBDUs) against tick bites was evaluated at four military training areas in southwestern and central Germany where tick bite incidence is known to be high. Data were analyzed by comparing tick bite incidence using non-permethrin-treated BDUs (NTBDUs) during 2009 versus PTBDUs during 2010 and 2011, the first two years after their formal introduction for in-country use in the German Bundeswehr. During 2009, 262 individual tick bites were reported at the four training sites, resulting in a tick bite incidence of 8.8 % per exposed person when wearing NTBDUs only. In 2010 and 2011, one tick bite case occurred under field conditions each year that PTBDUs were worn, corresponding to a protective effectiveness of 99.6 and 98.6 %. These data imply an annual tick bite incidence of 0.035 and 0.078 % per exposed person, respectively. Between 2010 and 2011, a 0.8 % decline in the protective effectiveness of PTBDUs was observed. Five tick bite incidents occurred while wearing non-impregnated parkas over correctly worn PTBDUs. Ixodes ricinus ticks were collected by standard tick drags from 2009 to 2011, with high mean annual densities ranging from 28.9 to 106.5 ticks per 100 m(2), while single drags revealed tick densities between zero and 381 ticks per 100 m(2). Overall, 4596 I. ricinus ticks (54 ♂, 82 ♀, 1776 nymphs, and 2684 larvae) were collected, of which 128 (2.8 %; mean annual range, 0-10.1 %) were Borrelia burgdorferi s.l. positive. The Borrelia genospecies distribution was as follows: 112 (87.5 %) Borrelia afzelii, 10 (7.8 %) B. burgdorferi s.s., and 6 (4.7 %) Borrelia garinii. Neither the tick density means from 2009 to 2011 nor associated B. burgdorferi s.l. prevalences differed significantly among the military locations investigated. The documented tick bite reductions clearly demonstrate the powerful protective effectiveness of properly worn PTBDUs against tick bites. Nevertheless, all apparel worn over PTBDUs should also be impregnated with permethrin in order to prevent tick infestation and subsequent bites.
authors.affiliation: Department of Medical Entomology / Zoology, Central Institute of the Bundeswehr Medical Service, PO box 7340, 56065, Koblenz, Germany, MichaelFaulde@bundeswehr.org.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Faulde
authors.forename: Martin
authors.initials: M
authors.lastname: Rutenfranz
authors.forename: Alexander
authors.initials: A
authors.lastname: Keth
authors.forename: Jürgen
authors.initials: J
authors.lastname: Hepke
authors.forename: Mareike
authors.initials: M
authors.lastname: Rogge
authors.forename: Andreas
authors.initials: A
authors.lastname: Görner
mesh_terms: D000818:Animals; D001898:Borrelia / Q000302:isolation & purification*; D003020:Clothing; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007306:Insecticides / Q000494:pharmacology*; D018884:Ixodes / Q000187:drug effects / Q000382:microbiology; D007814:Larva; D008297:Male; D008889:Military Personnel; D009758:Nymph; D016273:Occupational Exposure; D026023:Permethrin / Q000494:pharmacology*; D010865:Pilot Projects; D064927:Tick Bites / Q000453:epidemiology / Q000517:prevention & control; D013984:Tick Infestations / Q000453:epidemiology / Q000517:prevention & control*; D013987:Ticks / Q000187:drug effects* / Q000382:microbiology
chemical_list: D007306:Insecticides; D026023:Permethrin