How accurate are heartworm tests?

Heartworm antigen testing is perceived to be very accurate and precise, with specificity and sensitivity values for most tests reported to be >95%, and with specificity and sensitivity data approaching 100% when three or more adult worms are present.

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.

What happens if a dog has a positive heartworm test?

Once a dog tests positive on an antigen test, the diagnosis should be confirmed with an additional—and different—test. Because the treatment regimen for heartworm is both expensive and complex, your veterinarian will want to be absolutely sure that treatment is necessary. Restrict exercise.

What is a weak positive heartworm test?

A weakly positive in-clinic test result is likely positive, but the result can be confirmed by repeating the test or ordering a reference lab test. If results are discordant between in-clinic and laboratory tests, Dr. Herrin advises trusting the reference lab result.

How long before heartworm test is positive?

The earliest that the heartworm proteins can be detected in a dog’s bloodstream is about 5 months after it is bitten by an infected mosquito. Another test detects microfilariae in a dog’s bloodstream.

What are the first signs of heartworms in dogs?

Signs of heartworm disease may include a mild persistent cough, reluctance to exercise, fatigue after moderate activity, decreased appetite, and weight loss. As heartworm disease progresses, pets may develop heart failure and the appearance of a swollen belly due to excess fluid in the abdomen.

How often are heartworm tests false positive?

Such dogs, while often asymptomatic, can either have negative tests, positive tests or inconsistently positive tests. Recent studies have documented that antigen tests may not test positive in up to 7% of dogs due to the occurrence of “antigen-antibody complexes” that are formed in the dog’s blood.

Can a heartworm positive dog be around other dogs?

Heartworm disease is not contagious, meaning that a dog cannot catch the disease from being near an infected dog.

How long will a dog test positive for heartworms after treatment?

It is important to know that the heartworm test can remain positive for four-six months following treatment even if all worms were killed, so review the time line of your dog’s therapy.

Do dogs poop out heartworms?

The heartworm is one of the only mammal-dwelling parasites to be transmitted exclusively by mosquitoes. While other common parasitic worms are transferred via feces, heartworms cannot be passed directly from one host to another.

What kind of test is a heartworm test?

Heartworm tests are blood tests run to determine if an animal is infected with heartworms. The test may be run in-house or sent to a reference laboratory. If run in-house, results are often available in as little as 10 minutes.

What does heartworm positive mean?

A positive heartworm test means that your dog has adult heartworms. Left untreated, he will progress to heart failure and die, spreading heartworm larvae to every mosquito that bites him along the way, potentially infecting other unprotected dogs.

What does a heartworm test mean?

A heartworm test is only a test for heartworms . It is not to be confused with other diagnostic testing, like serum chemistry testing or blood sugar evaluation. When your vet staff tells you that the test result was negative, they only mean that the presence of ADULT heartworms was not detected.