Molecular and Clinical Evidence of Ehrlichia chaffeensis Infection in Cameroonian Patients with Undifferentiated Febrile Illness

摘要

Human monocytotropic ehrlichiosis (HME) is an emerging tick-transmitted zoonosis in the United States caused by Ehrlichia chaffeensis. Ehrlichia canis, E, chaffeensis and E. ewingii have recently been detected in dogs and Rhipicephalus sanguineus ticks from Cameroon; thus the potential exists for human infections. The objective of this study was to determine if Ehrlichia species were associated with acute fevers of unknown etiology in patients from the coastal region of Cameroon. E. chaffeensis was detected in peripheral blood from 12 (10%) of 118 patients using real-time polymerase chain reaction (PCR) amplification of the genus-specific disulfide bond (dsb) formation protein gene. Furthermore, DNA sequencing of PCR amplicons revealed that the dsb gene sequence was identical to E. chaffeensis (Arkansas strain). Patients with detectable E. chaffeensis DNA had clinical manifestations that included fever, headache, myalgia, arthralgia, pulmonary involvement, and diffuse rash.