Dog Parvo Diagnosis with PCR

Diagnosing dog parvo can be done to confirm a veterinarian’s initial diagnosis. There are other diseases that can present the same types of symptoms as parvovirus so it is often necessary to confirm the diagnosis. While the vomiting and diarrhea associated with parvo can cause the dog to decline quickly, running one of the diagnostic tests to confirm the diagnosis and provide a prognosis on the dog’s chances of recovery. One of the fastest, and most definitive of these tests is the polymerase chain reaction or PCR test.

Defining Parvovirus

Parvovirus is a viral infection that is spread to other dogs through contact with infected feces or ground. The virus begins to replicate in the dog’s lymph system and continues to progress through the bloodstream. As the infection develops it disrupts the dog’s digestive tract and allows anaerobic bacteria to leave the digestive tract and enter the bloodstream. Common symptoms of parvo are vomiting, diarrhea, dehydration, lack of interest in food and lack of energy. If the vomiting, diarrhea and dehydration can be controlled, the dog’s chances of survival can be increased. While parvo typically attacks dogs under one year old, those whose immune system hasn’t fully developed, it can affect older unvaccinated dogs.

Description of the PCR Test

The PCR test is available in two formats. The original test, PCR,  takes 2 to 4 days for results. The real-time test, RT-PCR, takes a few hours for results and is more definitive. The RT-PCR is also more accurate and can determine which strain of parvo the dog has. These advantages are important in a disease that can progress quickly like parvo.

The PCR is conducted on a stool sample from the affected dog. The dog’s body will try to rid itself of the virus and excrete it with the dog’s feces. Specific primers and enzymes are used on the sample with the resulting DNA product reviewed for parvo. Both the conventional and RT-PCR are capable of identifying parvo prior to the onset of symptoms, allowing treatment to begin early, potentially increasing the chance of survival.

The one drawback to both varieties of the PCR test is that it requires a laboratory environment and equipment to conduct the specific steps in the process, something typically not available at veterinary clinics.

Avoiding Parvovirus

The best way to avoid parvovirus infection in your dog is to ensure he is vaccinated against the disease. Puppies can begin receiving the vaccination at 6 weeks old and should receive additional vaccine every 3 to 4 weeks until they are 16 weeks old. The multiple vaccinations ensures that the mother’s antibodies haven’t killed the vaccine and the puppy’s body has started to build its own immunity. Annual vaccinations are recommended thereafter.

Confirming the diagnosis of parvo through testing can ensure your dog is receiving proper treatment. PCR testing can not only confirm the diagnosis, but can also identify the particular strain of parvo involved in the infection, allowing the veterinarian to develop a more defined prognosis and treatment. Providing proper supportive treatment can help return your dog to a healthy condition.