BY: SAMANTHA BARTLETT, DVM

The Companion Animal Parasite Council (CAPC) released the 2021 Pet Parasite Forecast in May. The ranges of ticks and mosquitoes have continued to expand across the United States leading to an increased risk of exposure to disease pathogens including heartworm, Lyme, Ehrlichia and Anaplasma spp. CAPC makes the forecast based on work done by parasitologists and statisticians who analyze positive tests for disease, influence of weather patterns, vegetation indices and the density of human populations. 

Heartworm prevalence is forecast to be higher along the Mississippi River, throughout southern Midwest and along the Atlantic Coast. CAPC cautions veterinarians in states with historically low incidence of heartworm to be aware of the increasing risk and to begin having conversations with their clients about the disease. This is particularly true for the interior Midwest and lower Great Lakes regions. 

Lyme disease has continued to progress southward and westward. Increases are expected in eastern Kentucky, northeastern Tennessee, western Michigan and Ohio. CAPC recommends that veterinarians in these regions as well as in regions that have historically high prevalence to encourage clients to be vigilant about tick control and prevention. 

The prevalence of Anaplasma species is expected to remain the same throughout most of the United States. CAPC does warn areas of Virginia, West Virginia, Texas and California to be vigilant to increases in prevalence in these areas. Ehrlichia has a variable range due to the many responsible species and prevalence is expected to remain high. Areas expected to see an increase include New Mexico, Arizona, California, Wyoming, Illinois, Wisconsin and Minnesota. 

The full report including prevalence maps and scientific methodologies can be found at https://capcvet.org/articles/risk-of-exposure-to-vector-borne-pathogens-what-to-expect-in-2021/.