Infection Rates of Amblyomma americanum and Dermacentor variabilis by Ehrlichia chaffeensis and Ehrlichia ewingii in Southwest Missouri
Abstract
Both Ehrlichia chaffeensis and Ehrlichia ewingii are causative agents of human ehrlichiosis. Both pathogens are transmitted to humans through the bite of an infected lone star tick (Amblyomma americanum). Since Missouri has a high incidence of human monocytic ehrlichiosis, we investigated the prevalence of E. chaffeensis- and E. ewingii-infected A. americanum and Dermacentor variabilis (American dog tick) ticks to help assess the relative risk for humans exposed to these vectors. We used a nested polymerase chain reaction assay for the detection of ehrlichial DNA in the collected ticks. Infection rates for both ehrlichial species were calculated from the assay results for each of the tick species. E. chaffeensis was found to be present in 9.8% of adult A. americanum ticks (57 of 579) and 6.7% of D. variabilis ticks (eight of 120). E. ewingii DNA was present at an infection rate of 5.4% in adult A. americanum (31 of 579) and 3.3% of D. variabilis ticks (four of 120). A minimum infection rate for nymph pools of A. americanum was 1.7% for E. chaffeensis and 0.6% for E. ewingii.
Department(s)
Biology
Document Type
Article
DOI
https://doi.org/10.1089/153036602321131841
Keywords
ehrlichia chaffeensis, ehrlichia ewingii, human monocytic ehrlichiosis, amblyomma americanum, dermacentor variabilis, tick infection Southwest Missouri
Publication Date
2002
Recommended Citation
Steiert, John G., and Felicia Gilfoy. "Infection rates of Amblyomma americanum and Dermacentor variabilis by Ehrlichia chaffeensis and Ehrlichia ewingii in southwest Missouri." Vector Borne and Zoonotic Diseases 2, no. 2 (2002): 53-60.
Journal Title
Vector Borne and Zoonotic Diseases