Ehrlichia spp. Forecast 2021

20210406 Capc Forecast Maps Display V1 Ehrlichiosis

Nationwide, the high prevalence areas for ehrlichiosis are less well-defined compared to other vector-borne pathogens. The maps represent multiple species within the genus Ehrlichia that may have differing geographical ranges. Nonetheless, prevalence is expected to be above normal for the majority of the United States with some interesting emerging risk areas.

  • Ehrlichia spp. seroprevalence in dogs is expected to remain high throughout the south-west, south-central, and coastal Atlantic states.
  • Several areas of increased risk for 2021 are evident in the forecast map. Increasing numbers of sero-positive dogs are expected in New Mexico, Arizona and southern California. Increases are also in the forecast for northern Colorado, southern Wyoming, the northern Rocky Mountain west, central and northeastern Illinois and parts of Wisconsin and Minnesota.
  • Considering the widespread prevalence of Ehrlichia spp. throughout much of the United States, the continued use of acaricides, routine examination of pets for the presence of ticks, and prompt removal remains imperative. Testing of symptomatic dogs can help monitor the prevalence of ehrlichiosis and will also help reinforce the use of available tick control products.

Year-round protection, annual testing

The best way to protect your patients is to advise owners of the importance of year-round prevention, even during the winter months. You can use the CAPC Parasite Prevalence Maps to support your recommendation by underscoring the risks in your area and in regions of the country your clients may travel with their pets. It is also critical to emphasize the importance of compliance and using products correctly.

CAPC Parasite Prevalence maps and Forecast maps are validated tools for increasing client willingness to engage in parasite prevention. Sign up to receive local alerts on parasite testing results down to the county level today by visiting the CAPC Parasite Prevalence Maps and selecting "Get Updates".

Monthly Pet Parasite Forecasts

Veterinary professionals and pet owners who want to monitor parasite activity in their county throughout the year, can also access 30-Day Parasite Forecast Maps at These maps, developed exclusively by CAPC, provide a local forecast for every county in the continental United States on a monthly basis.

The Science Behind the Forecasts

Vector-borne disease is dynamic and ever changing, driven by multiple factors that affect the development of arthropod vectors and the pathogens they carry. Leading parasitologists work in collaboration with a team of statisticians to identify regions of the country that may experience higher parasite incidence in the months ahead. Numerous factors are analyzed, including the number of positive tests and the influence of weather patterns, vegetation indices, and human population density. Using this multi-disciplinary approach, we are leveraging everyone’s expertise to focus on a single common interest: forecasting the risk of exposure to vector-borne pathogens. While these forecasts predict the potential risk of a dog testing positive, they do not necessarily reflect the occurrence of clinical disease.

To learn more about the science behind the maps, full access to our manuscripts describing the methodology and fidelity of our forecasts can be found here.