Parvovirus in Dogs

By: Dr. Sarah WootenUpdated:

Parvovirus in Dogs

Canine Parvovirus Infection: Understanding Parvo in Dogs

Spring is almost here, and while we love the longer days and sunlight, warmer temperatures bring about a seasonal resurgence in a deadly canine virus called parvovirus. Typically called parvo for short, parvovirus is so virulent that once a dog is infected, parvo can be fatal in less than 72 hours.

Parvo is caused by the canine parvovirus type 2 virus. Clients often ask me, “How do dogs get parvo?” Parvo in dogs is spread through direct contact with infected dogs and infected vomit and feces, and is easily carried on hands, food dishes, bedding and shoes. Parvovirus is a very successful virus—it is highly contagious and tough to kill, making it difficult to eradicate from the environment.

Parvo rapidly kills its host by attacking the gastrointestinal tract of puppies and dogs. Canine parvovirus infection causes severe dehydration, and bloody vomiting and diarrhea.  Parvo in dogs also attacks the immune system, weakening the dog’s ability to fend off bacterial infections. Dogs infected with parvo often die from secondary pneumonia or other bacterial infections.

Signs of Parvo in Puppies and Dogs

  • Lethargy or tiredness
  • Loss of appetite
  • Fever
  • Vomiting
  • Diarrhea, often bloody

Early in the course of infection, a dog infected with parvo can be easily overlooked, leading owners to delay treatment. The problem with waiting it out is that dogs become rapidly, devastatingly dehydrated and debilitated, more in need of costly urgent care, and less likely to survive. In the meantime, other dogs in the household are put at risk for infection. If  your puppy or dog is suffering from these signs, it is critical to take your dog to a veterinarian immediately.

Diagnosis and Treatment of Parvovirus

If your veterinarian suspects your puppy has parvovirus, he or she will most likely run a simple test that will confirm the infection. Your veterinarian may also run a complete blood count to see if the virus has affected the bone marrow, a fecal exam to look for intestinal parasites, and an internal organ blood screening test to check internal organ function.

Once an infection is confirmed, the virus must run its course. There is no cure for parvo, only supportive treatment with IV or subcutaneous fluids, anti-nausea medication and antibiotics to prevent other infections. If left untreated, parvo almost always means certain death; without treatment, more than 90% of dogs infected with parvovirus will die. Dogs that are hospitalized tend to have a higher recovery rate than dogs that are treated at home.

If your dog has been diagnosed with parvo, she should be isolated from all other dogs in the household until she has completely recovered. All bedding, food bowls and flooring should be disinfected with a dilute bleach solution, which eradicates the virus from the environment.

Preventing Parvo in Puppies and Dogs

There is good news, however! Parvovirus can easily be completely prevented with proper vaccination. The typical puppy series is three shots, given at 8 weeks, 12 weeks and 16 weeks. Even if your breeder has vaccinated your puppy before you brought him home, it is still necessary to get the series completed. Until your puppy has received a complete series of puppy boosters, he or she should be kept away from dogs with unknown vaccine histories, as well as dogs parks, groomers and pet stores. Adult dogs are typically vaccinated twice initially, then receive a one-year vaccination, and then every 3 years after that. Along with a healthy diet, proper exercise and a lot of love, vaccinations against deadly diseases like parvo are essential to help your dog live a long and healthy life.

Can Humans Get Parvo?

There has been no evidence that canine parvovirus can infect humans. Humans contract the B19 strain of parvovirus, typically called fifth disease, which causes a mild rash in children—but this is not the same strain as canine parvovirus. I have also been asked if canine parvovirus is the same virus that causes Ebola—to which I answer, “Good question!” While canine parvovirus and Ebola cause similar symptoms, the virus structure of canine parvovirus is very different from the Ebola virus, and they are not related.


By: Dr. Sarah WootenUpdated: