Incidence of heartworm disease has continued to rise not only in previously known hot spots but also in unexpected locations with previously low heartworm rates, according to the 2022 Heartworm Incidence Map from the American Heartworm Society (AHS). “For many pet owners—and even veterinarians—it can be all too easy to assume that heartworm isn’t common in their area,” Dr. Rizzo said. “A look at the AHS incidence map quickly dispels this assumption and makes it clear to owners that heartworm prevention is a ‘must’ for their pets.” While no single reason can be attributed to these changes, factors involved are believed to include a greater influx of heartworm-positive animals from out-of-state, higher testing rates, higher infection rates—or all three, according to the AHS.
