Why heartworm prevention messaging is becoming more urgent

Veterinary teams may need to rethink how they talk about heartworm prevention, not because the recommendation has changed, but because the risk picture keeps widening. In a dvm360 interview published April 29, 2026, American Heartworm Society president Marisa Ames, DVM, DACVIM, said practices should train the entire team to answer common questions, reinforce year-round prevention, and address persistent misconceptions, including that indoor pets or pets in colder climates face little risk. Her comments come just weeks after AHS released its 2026 heartworm incidence map, based on 2025 testing data, showing cases nationwide and new hot spots beyond traditional Gulf Coast and Southeast strongholds, with Texas leading the nation in incidence. (dvm360.com)

Why it matters: For veterinary professionals, the message is less about changing protocol and more about improving adherence. AHS says its recommendation for year-round nationwide prevention has been in place since 2010, and both AHS and CAPC continue to support year-round prevention rather than seasonal use. That makes communication strategy a clinical issue: missed doses, delayed refills, cost concerns, and low perceived risk all undermine prevention. Prior AHS commentary has linked rising incidence to poor compliance, and newer retrospective research found dogs with no recent preventive purchases were 6.7 times more likely to test positive than dogs with lapses, while U.S. transaction data showed average monthly-dose coverage of just 7.3 months per year. (aaha.org)

What to watch: Expect more practices to tie heartworm conversations to every wellness visit, annual testing, and teamwide client education as the latest incidence map reshapes local risk discussions. (heartwormsociety.org)