As a dog owner, you want to protect your loyal companion from any potential risks, and parvovirus definitely qualifies as a dangerous threat. Our team at Somerset Animal Hospital wants to educate you about this deadly illness, to ensure your dog is protected.

Parvovirus is a highly contagious virus that affects dogs

First discovered in 1978, parvovirus is a DNA virus that attacks rapidly dividing cells, such as those in the dog’s gastrointestinal tract and bone marrow. Infected dogs shed the virus, which is difficult to kill, in large amounts, and the pathogen can live in the environment for a long time. Parvovirus is therefore a significant threat to puppies, adolescent dogs, and unvaccinated dogs. The virus is spread from the mother in utero, or through contact with infected feces or contaminated objects, such as kennel floors, people’s hands, and dogs’ paws.

Dogs affected by parvovirus most commonly exhibit gastrointestinal signs

After a dog is infected, parvovirus incubates for three to seven days, during which the dog does not appear ill. While incubating, the virus rapidly multiplies in the lymph nodes and tonsils and invades the bloodstream, searching for rapidly dividing cells.

  • Bone marrow — The virus destroys young immune cells, causing a decrease in circulating protective white cells. This weakens the ability for the dog’s body to protect itself from infection.
  • Gastrointestinal (GI) tract — The virus does the most damage by targeting the small intestine’s epithelial lining, which absorbs nutrients, and prevents fluid loss and bacterial release from the GI tract into the bloodstream. Initial signs of damaged intestinal lining are severe vomiting and diarrhea. As the intestinal surface damage increases, fluid loss also increases, resulting in dehydration. Bacteria can leak through the compromised intestinal wall, causing infection throughout the body. 
  • Heart — In young puppies, the virus can affect the heart, causing inflammation in the heart muscle, a decreased ability to pump appropriately, and arrhythmias. Puppies affected by this condition exhibit difficulty breathing, because blood backs up into their lungs as their heart fails. Prognosis for affected puppies is poor.

Once the dog exhibits parvovirus signs, the first 24 to 72 hours are extremely critical. Initial signs include lethargy, fever, vomiting, and diarrhea. While parvovirus is not always fatal, dogs who succumb typically die from dehydration, shock, and sepsis.

Dogs affected by parvovirus are treated using supportive therapies

Once diagnosis is made, typically by signs exhibited and a fecal test, dogs affected by parvovirus will be placed on intravenous fluids to correct fluid losses. No cure exists for parvovirus, but dogs receiving sufficient supportive care have a good chance of survival. Other supportive treatments include:

  • Antiemetics to help prevent vomiting
  • Providing nutrition through a feeding tube
  • Plasma profusions to replace protein
  • Correcting electrolyte and glucose abnormalities 
  • Antibiotics, if bacteria have started to leak across the GI wall, or white blood cell counts are extremely low

Affected dogs will likely need hospitalization for several days. Monitoring their white blood cell count, blood glucose levels, and electrolytes will be necessary to provide suitable treatment. Without appropriate supportive therapy, more than half of affected dogs die. Dogs who survive the first 72 hours typically recover in five to seven days, depending on the illness severity.

While hospitalized, affected dogs will be kept in isolation to protect other dogs in the area from becoming infected. Dogs can shed the virus for up to two weeks after infection. Any area that housed an infected dog should be cleaned thoroughly using diluted bleach (i.e., 1 part bleach to 30 parts water). Parvovirus is resistant to many other common disinfectants. Any other household dogs should be tested for parvovirus and watched carefully for initial signs, such as fever and lethargy. After visiting an infected dog, you should dip your shoes in a bleach water bath, wash your hands thoroughly, and change clothes before being around other dogs.

Dogs can be vaccinated against parvovirus

While no vaccine is 100% effective, the canine parvovirus vaccination provides excellent protection, and appropriately vaccinated dogs are unlikely to become infected. Puppies typically receive the parvo vaccine in a combination shot starting at 6 weeks of age, followed by boosters every three to four weeks, until they are 16 weeks of age. After the initial course, dogs should receive a booster once a year. 

Until a puppy is fully vaccinated, they should not socialize with dogs whose vaccination status is questionable. On outings, do not allow your dog to contact other dog’s feces, and before you leave your dog at a boarding facility, ensure they require that dogs are appropriately vaccinated. 

Parvovirus is a dangerous and scary disease, but by keeping your dog current on their vaccines and maintaining good hygiene practices, you can prevent them from becoming a victim. If you would like to get your dog vaccinated, or if your dog is exhibiting parvovirus signs, do not hesitate to contact our team at Somerset Animal Hospital.