Canine parvovirus, also known as CPV or “parvo,” is a highly contagious disease infecting puppies and occasionally adult dogs. The disease can cause severe symptoms like vomiting, diarrhea and dehydration. The absence or delay of treatment can increase the risk of critical health complications including the possibility of death. Diagnostic testing plays a key role in detecting the virus early so veterinarians can start treatment.
“Canine parvovirus is a serious disease,” said Catherine Campbell, DVM, veterinary diagnostician at Texas A&M Veterinary Medical Diagnostic Laboratory, TVMDL.
“I emphasize the importance of vaccination and early intervention,” she said. “The key is to act quickly and to use all the tools we have at our disposal.”
Cell and tissue destruction
CPV causes devastation to the gastrointestinal tract by targeting rapidly dividing cells within the small intestine.
“They attack cells from the crypts of the villi that normally provide replacement cells for the intestinal lining,” Campbell said.
As a result of extensive cell loss, CPV disrupts nutrient absorption and fluid balance. The rapid fluid loss results in severe diarrhea, which is why infected dogs experience dangerously quick dehydration.
“The virus itself also targets bone marrow and lymphatic tissue,” Campbell said. “This can lead to immunosuppression and leave a puppy vulnerable to secondary infections, sepsis or even death.”
Campbell said dogs might begin to show symptoms sometime between three to seven days after infection.
A resilient virus
CPV is easily transmissible and can live in an environment for several months. The virus spreads through direct contact with the feces of infected dogs. It can also be transmitted via contaminated surfaces such as kennels, food and water bowls or even the hands and clothing of people who handle infected dogs.
“High risk environments include areas around puppies that are not well vaccinated or haven’t completed their [vaccine] series,” Campbell said.
Additionally, Campbell noted the importance for veterinarians to communicate the need for diligence when cleaning and disaffecting canine living environments. Furthermore, they should explain the resilience of CPV and why it is necessary to clean with appropriate disinfectant specifically formulated to kill the virus.
Detecting parvo with precision
Several veterinary clinics use the ELISA point-of-care test to detect the presence of the CPV antigen in the stool. This method is relatively inexpensive and produces results quickly. However, due to its high sensitivity, this test may produce false negatives when the viral load is low or when the sample is not sufficiently fresh to contain detectable levels of the virus.
“The point of care tests are excellent, but they’re not 100 percent accurate because it may be too early in the disease process,” Campbell said. “These tests are best utilized to confirm a diagnosis of parvovirus.”
TVMDL is equipped with high-precision diagnostic systems, designed to generate exceptionally accurate results. From March 2024 to March 2025 TVMDL tested 620 samples for CPV. Of this total, 557 were tested for CPV antibodies using the hemagglutination inhibition technique, and 63 were tested using PCR.
“The hemagglutination inhibition test is the gold standard test, and it actually checks for antibody level detection,” Campbell said. “It’s used more for checking to see if an animal is protected from parvovirus via vaccination or previous infection. PCR is for diagnosis of a sick animal, which is used for diagnosis of existing infection.”
Since there is not a cure for CPV, preventative practices, vaccine administration and supportive care are all notable tools when dealing with the viral disease. TVMDL serves as a resource housing state-of-the-art equipment specifically used to detect viral agents. Diagnostic results are powerful tools used to manage CPV and help veterinarians with fast, reliable confirmation to guide effective treatment against CPV.
For more information about canine parvovirus or TVMDL’s testing options, visit tvmdl.tamu.edu or call the College Station laboratory at 1-888-646-5623.
