EXPERIMENTAL BORRELIA-BURGDORFERI INFECTION IN PEROMYSCUS-LEUCOPUS

We evaluated the susceptibility of laboratory-reared adult and infant white-footed mice (Peromyscus leucopus) to a known pathogenic isolate of Borrelia burgdorferi (N40). Two-month-old and 3-day-old Peromyscus were inoculated intradermally with 10(6) to 10(7) spirochetes. At 21 d ays for adults or 30 days for infants post inoculation, mice were kill ed, and tissues were cultured for spirochetes and examined microscopic ally. Based on serology and culture, adult mice became infected but di d not have any gross or microscopic lesions. Mice inoculated as infant s became infected, and also developed carditis and multifocal arthriti s. Contact transmission between inoculated infants and their naive mot hers was not observed. Age at inoculation appeared to be a critical fa ctor in inducing Lyme borreliosis lesions in Peromyscus leucopus, as i n other species.