- Terrierman's Daily Dose -
I found this site to be particularly interesting. If you look at #3, it provides a link to the “
Seasonal Timing of Heartworm Chemoprophylaxis in the United States” by Dr. David Knight and James Lok of the American Heartworm Society. The blog and, more importantly, the article from these individuals from the American Heartworm Society would seem to imply that annual testing isn't necessary.
I don't mind spending whatever is necessary to keep my pets healthy. And I have to say, this heartworm test will probably by far be the least expensive thing I've ever had done at the vet's office. I do think it worth doing more research on whether it's necessary to feed poison to my pets every month, though.