Keeping your puppy safe from parvovirus

Canine parvovirus, or “parvo” as it’s commonly called, is one of the most significant health threats to puppies. Parvo is primarily a disease of the stomach and small intestine but can also affect a puppy's heart, bone marrow and lymphopoietic tissues (a big part of the immune system). 

The parvovirus attacks cells, impairs nutrient absorption and disrupts the pup’s gut barrier, so it’s important to contact your vet right away if your unvaccinated pup has been exposed. 

Parvovirus in puppies

According to Dr. Emily Singler, VMD, veterinary consultant for Fetch, the most common signs of parvovirus are diarrhea (that normally progresses to bloody diarrhea), vomiting, decreased energy and weakness, refusing to eat, weight loss and dehydration. Pet parents may also notice your pup has dry gums, is urinating less, has sunken eyes and is experiencing weakness. 

During a parvo infection, rapidly dividing cells, such as intestinal cells and bone marrow cells, are targeted by the virus. Viral attacks on these cells result in debilitating diarrhea and vomiting, as well as a drop in the defensive white blood cells usually produced by a puppy’s bone marrow to combat this type of infection. 

With parvo, a puppy can become fatally dehydrated. If the intestinal walls become damaged, bacteria from the intestinal tract can cross from the intestines into the bloodstream and cause sepsis, a severe systemic infection that’s often fatal.

How to prevent parvo in puppies

The good news is, we have excellent vaccines that can help protect against parvo. However, there’s a brief period before a puppy is eligible to receive vaccines where there’s a “switchover” between antibodies from the mother and effective vaccine protection. During this switchover time, any puppy can be vulnerable. Typically, vaccines start around 6-8 weeks of age and continue every 3-4 weeks until at least 16 weeks of age. Veterinarians recommend unvaccinated puppies avoid any potentially contaminated areas. 

“Puppies need to be vaccinated for parvo multiple times,” Dr. Singler says. “The reason for the multiple boosters is to make sure that each puppy gets at least one vaccine after their maternal immunity (antibodies from their mother) have worn off because these antibodies can interfere with how well the vaccine works. The parvo vaccine is considered a core vaccine, meaning that it’s recommended for most dogs regardless of their lifestyle or exposure risk.”

Once pups are fully vaccinated for parvo, they’re generally very well protected for the duration of immunity for the vaccine. For puppies, that’s usually about one year. Adult dogs that have been vaccinated likely need a parvo booster every 3 years.

Related: A beginners guide to puppy training

How do puppies get parvovirus

Since the virus is shed in the feces of infected dogs, you should avoid places where dogs commonly poop. This can include dog parks, common dog-walking trails, doggy daycare, groomers, kennels and even pet stores. 

“A puppy contracts parvo by ingesting the virus,” Dr. Singler says. “Since infected dogs shed the virus in their stool for up to 1 month and the virus can live in the environment for months, a puppy doesn’t have to have direct contact with an infected dog to become infected themselves.”

Whether or not you’re putting your puppy on the ground in public places, the risk of getting something on your own shoes or clothes is too great, so it’s truly best to avoid them until your pup is vaccinated.

Just as with puppies, adult dogs can also get parvo if they aren’t vaccinated or if they aren’t completely vaccinated. This means that if a dog only got one or two vaccines as a puppy and then never finished the series, they may not be fully protected.  

Some breeds seem to be more susceptible than others, but no dog breed is immune or resistant to parvo infection. Breeds reported to be more susceptible include Doberman Pinschers, rottweilers, German Shepherds, English Springer Spaniels and pitbulls. A dog who is naturally more susceptible to infection are at a higher risk of becoming sick if they aren’t completely vaccinated. 

How can you safely socialize your puppy?

So, where can you go to socialize your unvaccinated puppy without increasing their risk of getting parvo? Friends and relatives might have fully-vaccinated adult dogs that your puppy can get to know in a private backyard. 

Taking short leash walks around the neighborhood on the sidewalk is generally low risk as long as you keep your puppy from having contact with other dogs and their stool. They can definitely say hello to other people, though. 

If you have a yard that’s not used by dogs other than your own, this is a great place to start basic obedience training. It’s also a great place for your dog to be potty trained and to get their daily exercise.

What should you do if your puppy is exposed to parvovirus? 

There’s no treatment for the parvovirus itself, so it’s important to contact your vet if you think your pup may have been exposed. Your vet will work to prevent and correct severe dehydration and to prevent secondary bacterial infections, that can be fatal, in the bloodstream.  

“This type of treatment is often referred to as supportive treatment because we’re supporting the patient while their body’s immune system kills the virus,” Dr. Singler says. “Dogs and puppies with parvo typically need to be hospitalized on intravenous fluids for about 3-4 days. The fluids help to replace what puppies lose through vomiting, diarrhea and not eating.”  

Puppies with parvo also typically get medication to control and prevent vomiting, antibiotics to prevent a secondary bacterial infection and other medications as needed. Parvo is potentially fatal for puppies and dogs, so you should be sure to take any new pet to the vet right away, and continue vaccinations as recommended by your veterinarian.