When should my dog be tested for heartworms?

A dog should be tested once a year. All young dogs should start with testing at six to eight months of age using our current tests, only a test for the adult female worm. And those worms usually take six to eight months to mature, so we can't pick up those infestations until they're adult worms.

Your dog should be tested anywhere between six months and a year, depending on the hospital's preference, and then every year after that.

Your dog should be screened for heartworm disease every year during their annual wellness checkup. This ensures that any possible infections are caught early and appropriate treatment can be initiated.

Dogs under six months typically don't need testing. However, it is recommended to start prevention at eight weeks of age, which is when heartworm preventatives are labeled for use. It can take six months from when they're bitten by an infected mosquito for them to test positive. Testing for heartworm disease should start when your dog is six months of age and then semi-annually thereafter.

We recommend testing your dog for heartworms as soon as you foster or adopt them. However, if they're puppies, we usually don't test them until they're at least a year of age.