TRANSMISSION OF GRANULOCYTIC EHRLICHIOSIS
Principal Investigator: Sam Telford
Abstract: We propose to determine whether the agent of human granulocytic ehrlichiosis in coastal New England is cotransmitted with those of Lyme disease and human babesiosis. An Ehrlichia with molecular identity to one infecting humans in the upper Midwest was isolated from a Nantucket resident by subinoculation of her blood into laboratory mice. This agent stably infects intact or splenectomised outbred and inbred mice, as well as Peromyscus leucopus, the main enzootic reservoir of Borrelia burgdorferi and Babesia microti in the northeastern U.S. Nymphal deer ticks that had fed as larvae on experimentally infected mice transmitted the agent to uninfected mice, definitively demonstrating vector competence. Thus, we shall 1) determine the mode of perpetuation of the HGE agent in coastal Massachusetts, focusing on the hypothesis that borreliae, babesiae, and ehrlichiae share an enzootic cycle between rodent reservoirs and the deer tick vector; 2) refine our methods for detecting evidence of HGE infection in vertebrate and tick hosts, comparing microscopy-based methods (including immunohistochemistry) with a polymerase chain reaction assay; and 3) describe the public health burden of this emergent zoonosis relative to that of Lyme disease and babesiosis in various coastal New England communities, by retrospective analysis of a large serum bank, as well as by prospective cohort study. Together, these studies are designed to describe how humans become infected by this new zoonotic agent, and provide a basis for intervention.
Funding Period: 1996-08-01 - 2002-07-31
more information: NIH RePORT
- Hypersensitivity to ticks and Lyme disease riskGeorgine Burke
Connecticut Children s Medical Center, Hartford, Connecticut, USA
Emerg Infect Dis 11:36-41. 2005..14, 95% CI 0.94-0.03, p = 0.01). Prior exposure to uninfected vector ticks protects residents of disease-endemic sites from Lyme disease...
- Case records of the Massachusetts General Hospital. Case 10-2005. A 73-year-old man with weakness and pain in the legsHoward M Heller
Infectious Disease Unit, Massachusetts General Hospital, Boston, USA
N Engl J Med 352:1358-64. 2005
- Raccoons and skunks as sentinels for enzootic tularemiaZenda L Berrada
Tufts University Cummings School of Veterinary Medicine, North Grafton, Massachusetts 01536, USA
Emerg Infect Dis 12:1019-21. 2006..Skunks and raccoons were frequently seroreactive, whereas white-footed mice, cottontail rabbits, deer, rats, and dogs were not. Tularemia surveillance may be facilitated by focusing on skunks and raccoons...
- Fay and Rausch 1969 revisited: Babesia microti in Alaskan small mammalsHeidi K Goethert
Division of Infectious Diseases, Cummings School of Veterinary Medicine, Tufts University, North Grafton, Massachusetts 01536, USA
J Parasitol 92:826-31. 2006..Sequence analysis of the 18S rDNA gene demonstrates that Alaskan B. microti comprises a clade that infects microtines in several sites across North America and is distinct from a clade that is zoonotic...