Ehrlichia chaffeensis Infection in Coyotes
Ehrlichia chaffeensis Infection in Coyotes
A nested polymerase chain reaction assay was used to determine the presence of Ehrlichia chaffeensis, E. canis, and E. ewingii DNA in blood samples of free-ranging coyotes from central and north-central Oklahoma. Of the 21 coyotes examined, 15 (71%) were positive for E. chaffeensis DNA; none was positive for E. cani s or E. ewingii. Results suggest that E. chaffeensis infections are common in free-ranging coyotes in Oklahoma and that these wild canids could play a role in the epidemiology of human monocytotropic ehrlichiosis.
Human monocytotropic ehrlichiosis, a tick-borne zoonosis caused by the rickettsial pathogen Ehrlichia chaffeensis (Rickettsiales: Ehrlichieae), occurs primarily in the southern, south-central, and mid-Atlantic regions of the United States. The principal vector is the lone star tick, Amblyomma americanum (L.), and associations between the presence of the tick and the occurrence of human ehrlichiosis have been documented. The principal wildlife reservoir is the white-tailed deer (Odocoileus virginianus). Indeed, site-specific geographic and temporal associations have been made between the presence of A. americanum and E. chaffeensis antibodies in deer. No other wildlife species has been incriminated in the epidemiology of this disease, although serologic reactivity was detected in free-ranging raccoons (Procyon lotor) and opossums (Didelphis virginianus) from Georgia and white-footed mice (Peromyscus leucopus) from Connecticut. Additionally, red foxes (Vulpes vulpes) have been shown to be susceptible to infection under experimental conditions. Although some rodents have been experimentally infected with this pathogen, research findings about natural infections in wild rodent populations have been inconsistent. Domestic dogs are susceptible to both natural and experimental E. chaffeensis infections.
A nested polymerase chain reaction assay was used to determine the presence of Ehrlichia chaffeensis, E. canis, and E. ewingii DNA in blood samples of free-ranging coyotes from central and north-central Oklahoma. Of the 21 coyotes examined, 15 (71%) were positive for E. chaffeensis DNA; none was positive for E. cani s or E. ewingii. Results suggest that E. chaffeensis infections are common in free-ranging coyotes in Oklahoma and that these wild canids could play a role in the epidemiology of human monocytotropic ehrlichiosis.
Human monocytotropic ehrlichiosis, a tick-borne zoonosis caused by the rickettsial pathogen Ehrlichia chaffeensis (Rickettsiales: Ehrlichieae), occurs primarily in the southern, south-central, and mid-Atlantic regions of the United States. The principal vector is the lone star tick, Amblyomma americanum (L.), and associations between the presence of the tick and the occurrence of human ehrlichiosis have been documented. The principal wildlife reservoir is the white-tailed deer (Odocoileus virginianus). Indeed, site-specific geographic and temporal associations have been made between the presence of A. americanum and E. chaffeensis antibodies in deer. No other wildlife species has been incriminated in the epidemiology of this disease, although serologic reactivity was detected in free-ranging raccoons (Procyon lotor) and opossums (Didelphis virginianus) from Georgia and white-footed mice (Peromyscus leucopus) from Connecticut. Additionally, red foxes (Vulpes vulpes) have been shown to be susceptible to infection under experimental conditions. Although some rodents have been experimentally infected with this pathogen, research findings about natural infections in wild rodent populations have been inconsistent. Domestic dogs are susceptible to both natural and experimental E. chaffeensis infections.