title: Dermatologic changes induced by repeated Ixodes scapularis bites and implications for prevention of tick-borne infection.
abstract: Previous studies in rodents and people have demonstrated that repeated tick exposure is associated with reduced Borrelia burgdorferi transmission but the mechanism of prevention remains unclear. We examined the acute histopathologic reactions to initial and repeated Ixodes scapularis bites in BALB/c mice and in people. Skin biopsies of BALB/c mice infested for the first time by I. scapularis nymphs revealed vascular dilatation and an accumulation of inflammatory cells adjacent to the bite site but absent at the site of tick attachment. Such changes would enhance tick-borne pathogen transmission. Mice reexposed to I. scapularis nymphs experienced a decrease in vascular dilatation and a marked increase in inflammatory cells at the site of tick attachment. Skin biopsies of people with attached I. scapularis nymphs revealed similar histologic patterns. These results indicate that cellular changes at the tick-dermal interface following I. scapularis attachment are likely to allow for successful transmission of tick-borne pathogens in non-tick-immune hosts and to inhibit tick-borne pathogen transmission in hosts that have developed tick immunity.
authors.affiliation: University of Connecticut School of Medicine, Farmington, Connecticut, USA. peter.krause@yale.edu
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Krause
authors.forename: Jane M
authors.initials: JM
authors.lastname: Grant-Kels
authors.forename: Steven R
authors.initials: SR
authors.lastname: Tahan
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Dardick
authors.forename: Francisco
authors.initials: F
authors.lastname: Alarcon-Chaidez
authors.forename: Keith
authors.initials: K
authors.lastname: Bouchard
authors.forename: Christine
authors.initials: C
authors.lastname: Visini
authors.forename: Cindy
authors.initials: C
authors.lastname: Deriso
authors.forename: Ivo M
authors.initials: IM
authors.lastname: Foppa
authors.forename: Stephen
authors.initials: S
authors.lastname: Wikel
mesh_terms: D000818:Animals; D001733:Bites and Stings / Q000150:complications*; D004195:Disease Models, Animal; D004478:Ectoparasitic Infestations / Q000473:pathology* / Q000635:transmission / Q000662:veterinary; D006801:Humans; D018884:Ixodes; D051379:Mice; D008807:Mice, Inbred BALB C / Q000469:parasitology; D017282:Tick-Borne Diseases / Q000517:prevention & control