Bovine Petechial Fever

Abstract

Bovine petechial fever, caused by Ehrlichia ondin, occurs sporadically in highland areas of Kenya, particularly affecting exotic breeds of cattle. There is a marked spatial restriction on disease occurrence, often to areas as small as part of a paddock, and usually associated with forest edge or scrub. Ehrlichia ondin can be harbored by bushbuck and possibly other wild ruminants, and may be transmitted by an arthropod vector.

The disease is clinically marked by fever and widespread petechiation of mucous membranes. At necropsy, edema and lymphoid hyperplasia are evident in addition to widespread hemorrhages. Diagnosis depends on demonstration of E. ondin, either by examination of Giemsa-stained blood smears, or by inoculation of tissues to susceptible sheep.

It may be possible to protect valuable animals by artificial infection followed by treatment with a dithiosemicarbazone. Generally, control depends on keeping cattle away from known infected areas, and clearing undergrowth and scrub.