Gastrointestinal problems are common in puppies, and whether from indiscriminate diets, foreign objects or viral infections, vomiting and diarrhea can be mild or very serious. Parvo is a virus that is contagious from dog to dog. This virus invades the intestinal lining, resulting in profound illness. A parvo test can help determine whether parvovirus is the cause of the dog's illness, and the most practical method for diagnosis is the ELISA test. Sample collection is taken by rectal swab. A parvo test is indicated in any puppy with gastrointestinal illness, regardless of vaccination status.

There are no real contraindications to performing this test in an ill puppy.

What Does a Parvo Test Reveal?

A parvo test reveals the presence of parvovirus antigen in your dog's feces. If infected with the parvovirus, the body's immune system mounts a response in an attempt to fight off the infection. Antigens are formed and can be detected by the parvo test. Shortly after vaccination (5 to 17 days) with the parvo vaccine, parvo antigen can be shed and may result in false positive test results.

Though uncommon, false negatives can occur. If the diarrhea has a lot of blood in it, the antibodies in the blood may bind with the parvo antigens in the stool, inactivating the antigen and causing a false negative test result.

How Is a Parvo Test Done?

In order to perform a parvo test, your veterinarian will use a special cotton tip applicator to obtain a sample from your dog's rectum. Using a sample directly from the rectum is preferred, since the viral antigens are concentrated in the cells lining the rectum. Tests performed on voided feces may result in false negatives since the cells lining the rectum are not typically shed in the feces. After obtaining the sample, the applicator is placed in a special test solution. A portion of this solution is then placed in the test kit. The results are based on a color change on the test paper, similar to a human at-home early pregnancy test.

Many veterinarians are able to perform the parvo test in the hospital setting. For some, the sample is submitted to an outside laboratory for evaluation. Test results may not be available for up to one or two days.

Is a Parvo Test Painful?

Any discomfort involved is associated with the collection of the sample. An applicator is placed in the rectum, which may be uncomfortable, but not painful.

Is Sedation or Anesthesia Needed for a Parvo Test?

Neither sedation nor anesthesia is needed to obtain the sample or perform the test.