EXPERIMENTAL-INFECTION OF THE HUMAN GRANULOCYTIC EHRLICHIOSIS AGENT IN HORSES

Human blood collected from two patients from Westchester County, New Y ork with human granulocytic ehrlichia (HGE) infection was inoculated i nto two ponies, Inoculated ponies developed clinical signs similar to a previous report (Madigan et al., 1995). Histopathological changes in volved follicular hyperplasia of lymphoid tissues, I-ICE DNA was detec ted by PCR in muscle, fascia, peritoneum, and adrenal gland after the ponies produced a high level of antibodies to HGE. We suggest that I-I CE may reside in poorly vascularized connective tissues, where the ant ibodies may have some difficulties to penetrate, resulting in persiste nt infection. Since HGE and E. equi cause very similar diseases in bot h humans and horses, they may be the same organism with minor genetic differences. (C) 1998 Elsevier Science B.V.