Open Access Highly Accessed Research

Seroprevalence of Ehrlichia canis, Ehrlichia chaffeensis and Ehrlichia ewingii in dogs in North America

Melissa J Beall1*, A Rick Alleman2, Ed B Breitschwerdt3, Leah A Cohn4, C Guillermo Couto5, Michael W Dryden6, Lynn C Guptill7, Cristina Iazbik5, Stephen A Kania8, Patty Lathan9, Susan E Little10, Alma Roy11, Katherine A Sayler2, Brett A Stillman1, Elizabeth G Welles12, Wendy Wolfson11 and Michael J Yabsley13

Author Affiliations

1 IDEXX Laboratories, Inc., Westbrook, ME, USA

2 University of Florida, College of Veterinary Medicine, Gainesville, FL, USA

3 North Carolina State University, College of Veterinary Medicine, Raleigh, NC, USA

4 University of Missouri, College of Veterinary Medicine, Columbia, MO, USA

5 The Ohio State University, College of Veterinary Medicine, Columbus, OH, USA

6 Kansas State University, College of Veterinary Medicine, Manhattan, KS, USA

7 Purdue University, College of Veterinary Medicine, West Lafayette, IN, USA

8 University of Tennessee, College of Veterinary Medicine, Knoxville, TN, USA

9 Mississippi State University, College of Veterinary Medicine, Mississippi State, MS, USA

10 Oklahoma State University, College of Veterinary Medicine, Stillwater, OK, USA

11 Louisiana State University, College of Veterinary Medicine, Baton Rouge, LA, USA

12 Auburn University, College of Veterinary Medicine, Auburn, AL, USA

13 University of Georgia, College of Veterinary Medicine, Athens, GA, USA

For all author emails, please log on.

Parasites & Vectors 2012, 5:29  doi:10.1186/1756-3305-5-29

Published: 8 February 2012

Abstract

Background

This study evaluated the exposure of dogs to three different Ehrlichia spp. in the south and central regions of the United States where vector-borne disease prevalence has been previously difficult to ascertain, particularly beyond the metropolitan areas.

Methods

Dog blood samples (n = 8,662) were submitted from 14 veterinary colleges, 6 private veterinary practices and 4 diagnostic laboratories across this region. Samples were tested for E. canis, E. chaffeensis and E. ewingii specific antibodies using peptide microtiter ELISAs.

Results

Overall, E. canis, E. chaffeensis and E. ewingii seroprevalence was 0.8%, 2.8%, and 5.1%, respectively. The highest E. canis seroprevalence (2.3%) was found in a region encompassing Arkansas, Louisiana, Oklahoma, Tennessee and Texas. E. chaffeensis seroreactivity was 6.6% in the central region (Arkansas, Kansas, Missouri, and Oklahoma) and 4.6% in the southeast region (Georgia, Maryland, North Carolina, South Carolina, Tennessee and Virginia). Seroreactivity to E. ewingii was also highest in the central region (14.6%) followed by the southeast region (5.9%). The geospatial pattern derived from E. chaffeensis and E. ewingii seropositive samples was similar to previous reports based on E. chaffeensis seroreactivity in white-tailed deer and the distribution of human monocytic ehrlichiosis (HME) cases reported by the CDC.

Conclusions

The results of this study provide the first large scale regional documentation of exposure to E. canis, E. chaffeensis and E. ewingii in pet dogs, highlighting regional differences in seroprevalence and providing the basis for heightened awareness of these emerging vector-borne pathogens by veterinarians and public health agencies.

Keywords:
Ehrlichia; E. canis; E. chaffeensis; E. ewingii; dog; tick; prevalence