Can dogs have heartworm and test negative?

A. It’s possible for dogs to test antigen-negative and microfilaria-positive (e.g. with immune complex formation) or antigen-positive and microfilaria-negative (e.g. during an occult infection). Conducting both antigen and microfilaria tests helps ensure that heartworm diagnoses will not be missed.

Can you get a false negative heartworm test?

The antigen test detects a substance produced by heartworms. They are the fastest and most convenient way to test for heartworms, but no test is perfect. False positives and false negatives are possible. That is why positive tests are always confirmed with another method of testing.

How common is a false negative heartworm test?

Early infestations, very low numbers of parasites, and infestation with mostly male worms are the most common causes of false negatives. False negative heartworm tests are rare.

Are dog heartworm tests necessary?

Annual testing is necessary, even when dogs are on heartworm prevention year-round, to ensure that the prevention program is working. Heartworm medications are highly effective, but dogs can still become infected. If you miss just one dose of a monthly medication—or give it late—it can leave your dog unprotected.

How can I tell if my dog has heartworms?

Although it can be hard to tell when a dog has heartworms, the signs of puppy heartworms are a little clearer. Most puppies with heartworms will have trouble breathing, and cough a lot. They also have a hard time gaining weight, and often have very low energy.

How often should dogs have heart worm tests?

It is very important to get dogs tested for heartworms at least once a year. Puppies can start on heartworm preventative from 6 to 8 weeks old. Most vets recommend putting dogs on a heartworm medication such as heartguard that is taken once a month.

What do you do for dog that has heartworms?

Surgery may be required to rid a dog of a heartworm. A dog might exhibit no signs of heartworms. Veterinarians recommend giving animals heartworm pills to prevent a heartworm infection, which can be expensive and difficult to treat.

How does vet. check for heartworms in dogs?

Heart worm disease in dogs is screened for very easily and quickly with a blood test. Basically a few drops of blood is drawn and this is then placed with a reagent to run across an Eliza test in the clinic to screen for antigen specific for the heart worm.