How Vets Check for Parvo in Dogs

If you're at the dog park minding your business and you hear the word parvo, you might want to find out what people are talking about. Parvo is short for parvovirus, which is sometimes called canine parvovirus or CPV.

Using A Stethoscope
How Vets Check for Parvo in Dogs
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Parvo is a dangerous and highly contagious disease that can affect dogs that spend time together at a dog park, a doggy day care, or other communal places such as shelters. Unfortunately, dogs can die of parvo. Getting your dogs vaccinated for parvo when they are old enough and keeping your dogs away from areas where parvo is known to be are important preventative tools.

How do dogs get parvo?

Canine parvovirus is called CPV in the Merck Veterinary Manual. That book explains that other dogs are exposed to the virus through the feces of infected dogs. As non-infected dogs sniff or lick at infected feces, they expose themselves to the virus. The virus is not affected by temperature changes, nor is it affected by typical cleaners and detergents.

The American Veterinary Medical Association (AVMA) says that in kennels or shelters where dogs are in close contact with other infected animals, surfaces such as food and water bowls, collars and leashes, and the hands and clothing of people who handle infected dogs can spread the virus. This also means it is possible for one dog in a household to be exposed and for other dogs within the household to become infected.

CPV can live indoors for up to two months and outdoors for several months. Because of the hardy nature of this virus and its long life, places like dog parks that are affected by parvo poop are often closed. Never ignore a warning sign about a dog park being closed due to parvo if you are looking for a place to take your dog!

How to test for parvo

The American Kennel Club says that a veterinarian's diagnosis of parvovirus is done through analysis of symptoms and blood testing. A veterinarian can use a test called ELISA to look for evidence of the virus in your dog's feces. According to Mar Vista Animal Center in Los Angeles, Calif., ELISA stands for Enzyme Linked ImmunoSorbent Assay.

The ELISA parvo test can be performed in the veterinarian's office in about 15 minutes, and the tests are very sensitive to the presence of the virus. The parvo blood test looks for a reduction of white blood cells. The virus lowers the immune system response by preventing white blood cells from being formed in the bone marrow. An active infection will show a drop in white blood cell count when the blood is examined.

While vomiting and diarrhea are common signs of parvo in dogs, there are other causes of these symptoms as well. The Mar Vista Animal Center reminds dog owners that a recent vaccination for the parvo virus can sometimes result in a false positive. If your dog does need to have a parvo test, let the veterinarian know if your animal has been vaccinated within five to 12 days prior.

PCR testing for parvo

PCR testing, or Polymerase Chain Reaction testing, is a newer method of checking for parvo. For this test, a sample of feces is required. A laboratory test will look for evidence of parvovirus DNA in the poop. If your dog does have parvo poop, this PCR test will detect even very small amounts of the virus. This method is not done in the veterinary office while you wait.

The antibody titer test

The Mar Vista Animal Center says that another way of checking for parvo is to run an antibody titer test. As more clinics use ELISA testing, this testing is no longer as common. The antibody titer is a test that detects the presence and measures the amount of antibodies within a blood sample. A high IgM titer indicates an active infection.

Parvo in puppies

Puppies are most vulnerable to parvo. Parvo in puppies generally occurs in puppies who are six weeks to six months old and are unvaccinated or who are not completely vaccinated. Puppies can start getting their shots at six weeks of age. Puppies receive a parvo vaccine at six, eight, and 12 weeks, according to the American Kennel Club.

If you have a new puppy in your house, keep them protected from places like dog parks where a lot of other animals go until they are able to be fully vaccinated, which means receiving all three shots in the parvo series. The AKC also recommends that puppies receive an additional canine parvovirus vaccine between 14 and 16 weeks of age, even if they got the other doses, to develop even more protection.

Parvo symptoms

Parvo affects the cells that line the intestines. This is why diarrhea and other intestinal issues are among the first to appear after infection. The AVMA says symptoms progress rapidly once they do start to show up. The AVMA also says that most deaths from parvovirus occur within 48 to 72 hours following the appearance of symptoms.

The American Kennel Club lists several symptoms of parvo in puppies. Any of these symptoms could be serious, so the sooner you get your puppy to the veterinarian the better:

  • Bloody diarrhea
  • Vomiting
  • Fever
  • Lethargy
  • Anorexia
  • Weight loss
  • Weakness
  • Dehydration
  • Depression

If you think your puppy has been exposed to parvo, let the vet know when you call because they will want to limit the possibility of other dogs being exposed to it while you are having your visit. The Canine Journal says that parvo incubates for five to 10 days. Your dog will begin to show symptoms within 10 days of being exposed to the parvo virus. The most common symptoms are fever, lethargy, vomiting, and diarrhea.

Breeds at risk of parvo

The AKC also says that certain dog breeds are more likely to be vulnerable to parvo than other dog breeds. These breeds seem to be at increased risk for parvo for an unknown reason:

  • Rottweilers
  • Doberman pinschers
  • American Staffordshire terriers
  • English springer spaniels
  • German shepherds
  • Labrador retrievers

Cure for parvo?

There is no cure for parvo. Treatment of parvo will mean helping your dog's immune system improve, so he or she can fight off the infection on his or her own. Leo's Pet Care says the survival rate of untreated parvo is less than 25 percent.

What is parvo poop?

Sometimes people will talk about checking their dog's poop for parvo. They think they can tell by the smell if their dog has "parvo poop." Leo's Pet Care says this is a myth. Leo's Pet Care says parvo poop does not smell a certain way, so that can't be used to make a diagnosis.

Bloody feces is serious, but it might not be parvo. But any issue that causes diarrhea in a dog should not be ignored. Even if you don't think it's parvo, it's worth getting your dog checked out at the vet.