Heartworms are prevented by taking a prescribed preventative, which can be administered monthly, semi-annually, or even annually.

Yes, even indoor dogs can get heartworms, as well as cats. Mosquitoes can still be found indoors, so there is still a risk for indoor dogs. It is much easier to prevent than to treat heartworm disease, so it is recommended to keep your dog on prevention year-round, regardless of whether they are indoor-only, inside-outside, or outside-only.

The cycle of heartworms starts when a mosquito carrying the infected larva bites your dog and deposits the infected larva into the tissue. The infected larva then spreads to the heart, where the adult heartworm develops. Heartworm preventatives help clear the baby heartworms or infected larva, but none of the preventatives treat the adult stage.

Heartworms are most common in the Mississippi Delta down to the Louisiana area, which has the highest number of heartworm cases in the entire country. If you live in this area, your dog should be on heartworm prevention year-round because it is incredibly common.

No, a dog cannot pass on heartworms directly to another dog or a person. It requires a mosquito to bite the infected dog, get the infected larva, and then bite another dog, depositing the infected larva for it to be spread. Heartworm disease is not spread to humans.

Yes, dogs on prevention still need a yearly heartworm test. There are some resistant strains of heartworm, so it is crucial to ensure that your dog is truly negative and that the heartworm preventative is effective. It is recommended to check twice a year, as that's how long it can take for them to test positive after being bitten by an infected mosquito.

The most accurate heartworm test is the external lab tests. In-clinic tests are also very accurate, with roughly 98 to 99 percent accuracy.

There is a confirmatory test that can be sent to an outside lab. The in-clinic tests are very accurate and sensitive, usually around 98 to 99 percent accurate. However, if a pet has consistently been on heartworm prevention and tests positive, a confirmatory test will often be sent out to make sure before starting treatment that they are truly positive.

It is recommended to test your dog twice a year for heartworms. Mississippi and Louisiana have the highest incidence of cases of heartworm disease in dogs in the United States. There are some reports of resistant strains of heartworm disease in Louisiana, so it is essential to ensure that the heartworm prevention products are effective.

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.