Analysis of genetic identity of North American Anaplasma phagocytophilum strains by pulsed-field gel electrophoresis.

Biological and geographic heterogeneity of anthropozoonosis caused by Anaplasma phagocytophilum is poorly understood. Seven North American A. phagocytophilum strains were compared by PFGE.

ankA: an Ehrlichia phagocytophila group gene encoding a cytoplasmic protein antigen with ankyrin repeats.

Human granulocytic ehrlichiosis (HGE) is a potentially fatal, tick-borne disease caused by a bacterium related or identical to Ehrlichia phagocytophila. To identify and characterize E. phagocytophila group-specific protein antigen genes, we prepared and screened HGE agent and Ehrlichia equi genomic DNA expression libraries using polyclonal equine E.

Experimental inoculation with human granulocytic Ehrlichia agent derived from high- and low-passage cell culture in horses.

We report the successful infection throughout intravenous inoculation with low and high passage of in vitro-grown human granulocytic ehrlichiosis (HGE) agent in horses. Differences in disease severity but not in incubation time, hematological changes, PCR detection, ehrlichial load, seroconversion time, and titer range were noted between horses infected with a low and a high passage of in vitro-grown HGE agent.

Improved sensitivity of PCR for diagnosis of human granulocytic ehrlichiosis using epank1 genes of Ehrlichia phagocytophila-group ehrlichiae.

The agent of human granulocytic ehrlichiosis (HGE), Ehrlichia phagocytophila, and Ehrlichia equi probably comprise variants of a single Ehrlichia species now called the Ehrlichia phagocytophila genogroup. These variants share a unique 153-kDa protein antigen with ankyrin repeat motifs encoded by the epank1 gene. The epank1 gene was investigated as an improved target for PCR diagnosis of HGE compared with the currently used 16S rRNA gene target.

Seroprevalence of human granulocytic ehrlichiosis among permanent residents of northwestern Wisconsin.

Four-hundred seventy-five permanent residents of Wisconsin were tested for antibodies to the agent of human granulocytic ehrlichiosis (HGE) by indirect immunofluorescent antibody (IFA) testing with Ehrlichia equi as antigen marker. Each resident completed a standard survey questionnaire about outdoor activities, animal and tick exposure, and any febrile illness during the preceding 12 months. Seventy-one serum samples (14.