Detection of attenuated, noninfectious spirochetes in Borrelia burgdorferi-infected mice after antibiotic treatment
ABSTRACT Xenodiagnosis by ticks was used to determine whether spirochetes persist in mice after 1 month of antibiotic therapy for vectorborne Borrelia burgdorferi infection. Immunofluorescence and polymerase chain reaction (PCR) were used to show that spirochetes could be found in Ixodes scapularis ticks feeding on 4 of 10 antibiotic-treated mice up to 3 months after therapy. These spirochetes could not be transmitted to naive mice, and some lacked genes on plasmids correlating with infectivity. By 6 months, antibiotic-treated mice no longer tested positive by xenodiagnosis, and cortisone immunosuppression did not alter this result. Nine months after treatment, low levels of spirochete DNA could be detected by real-time PCR in a subset of antibiotic-treated mice. In contrast to sham-treated mice, antibiotic-treated mice did not have culture or histopathologic evidence of persistent infection. These results provide evidence that noninfectious spirochetes can persist for a limited duration after antibiotics but are not associated with disease in mice.
- SourceAvailable from: oxfordjournals.orgThe Journal of Infectious Diseases 06/2003; 187(10):1676; author reply 1676. DOI:10.1086/374939 · 5.78 Impact Factor
- The Journal of Infectious Diseases 06/2003; 187(10):1675-6. DOI:10.1086/374938 · 5.78 Impact Factor
Article: Canine borreliosis.[Show abstract] [Hide abstract]
ABSTRACT: A guild of organisms carried by the same vector (Ixodes ticks) in Lyme-endemic areas may be confounding the understanding of Lyme disease in dogs. A new diagnostic method, the C6 peptide test for Lyme, and serology and PCR testing for Ehrlichia, Babesia, and Bartonella species will help to sort out seroprevalence and symptomatology caused by exposure to these agents or by coinfections. In addition, Rickettsia, Leptospira, Mycoplasma species, and more could be involved in dogs diagnosed with a "doxycycline-responsive" disease. The author does not recommend treating asymptomatic Borrelia carrier dogs, but does recommend screening them for proteinuria and for exposure to other agents. A positive Lyme titer is a marker of exposure to Ixodes ticks and the agents they carry. The risk/benefit of vaccination will be understood better as the symptomatology and immunopathogenesis of Lyme disease are defined. Meanwhile, tick control is highly recommended for all dogs in Lyme-endemic areas.Veterinary Clinics of North America Small Animal Practice 08/2003; 33(4):827-62. DOI:10.1016/S0195-5616(03)00037-8 · 1.04 Impact Factor