Parvovirus in dogs and puppies


  • Parvovirus (parvo) is a nasty virus that causes severe diarrhoea and vomiting in dogs.
  • Parvovirus is still common in the UK and can be deadly if it’s left untreated.
  • Our PDSA Pet Hospitals see nearly 1,500 cases of parvo each year.
  • Fortunately, you can protect your dog by regularly vaccinating them against parvovirus.

General information

Parvovirus is a nasty virus that attacks the intestines causing severe vomiting, diarrhoea and dehydration in dogs. It’s very contagious and spreads in poo particles. Unvaccinated puppies, less than 6 months old, are particularly prone to parvovirus infections and often get the most severe signs.

Fortunately, we can protect our dogs from parvovirus by vaccinating them regularly throughout their life.

Illustration showing parvovirus in dogs

Parvovirus attacks the lining of the guts. It causes severe pain, bloody diarrhoea and vomiting. Click image to enlarge.


Parvovirus symptoms include:

When to contact your vet

Contact your vet for an emergency appointment if your dog develops parvovirus symptoms. Wait outside the clinic with your dog until you are called to prevent spreading parvovirus to dogs in the waiting room.

If your dog has had contact with an infected dog, monitor them closely for symptoms and call your vet for advice if you are concerned.


Treatment involves supporting your dog’s body while it fights the virus because unfortunately, there is no specific medicine to treat parvovirus and antibiotics don’t work because it’s a virus not a bacteria.

  • Intensive nursing and feeding. Your dog will need to be carefully nursed in a veterinary hospital. They will be kept clean, warm, fed and hydrated. If your dog can’t or won’t eat, they may need to be fed through a stomach tube. They will also need to be kept away from other dogs to prevent them picking up any other infections or spreading parvovirus.
  • A fluid drip. Your dog will need a fluid drip (fluids given straight into the blood stream) to replace the fluids they are losing in their diarrhoea/vomit. Without a drip your dog may becoming dangerously dehydrated.
  • Antibiotics. Antibiotics won’t kill parvovirus but are often used to protect against other infections during recovery.
  • Other medications. Other medications such as anti-sickness and stomach ulcer medication may be necessary.

Outlook and survival rate

Your dog’s chance of surviving parvovirus is much higher if you take them to the vet as soon as you notice symptoms. Most dogs who receive veterinary treatment quickly survive parvo, but it’s often fatal without treatment. Sadly, because it’s such a nasty disease, some dogs die from parvo even if they are treated quickly.


If your dog improves enough to return home, you will need to nurse them while they continue recovering, you will need to make sure that they:

  • Drink little and often.
  • Eat small, bland meals throughout the day (ask your vet which food is best).
  • Get lots of rest (walks won’t be necessary until they are feeling much better).
  • Have constant access to somewhere they can wee and poo (they will need to go more regularly than usual).
  • Are kept away from other dogs and public spaces for a few weeks after they have recovered (this is to protect them from picking up any other illnesses and also to prevent them spreading parvovirus to other dogs, which can happen for a few weeks after they recover).

How do dogs catch parvo?

Unvaccinated dogs (unvaccinated puppies are most at risk) can catch parvovirus from an infected dog, an infected dog poo or anything an infected dog has touched such as a dog lead, food bowl, bedding, human hands and clothes.

Dogs that are lucky enough to survive a parvovirus infection are often infectious for a few weeks after they recover, and the virus can then live in the environment for up to a year.

If you have recently lost a dog to parvovirus, speak to your vet about what steps you need to take before bringing a new dog or puppy into your home.

Illustration showing how parvo is spread

Dogs can spread parvo for weeks after they recover. Click image to enlarge.

Preventing parvovirus

Vaccination. Parvovirus spreads in poo particles and can live in the environment for up to a year. For this reason, it’s very important to have your dog vaccinated regularly to keep them protected from this invisible threat. Adult dogs need boosters regularly throughout their life, speak to your vet for more information about vaccinations.

Buy and rehome responsibly. Always buy from a responsible breeder or reputable rehoming centre. If you are getting a puppy, make sure you see the litter with their mum and check that she’s up to date with her vaccines. All the puppies should be healthy and bright with no signs of illness.

Taking an unvaccinated puppy outside

An unvaccinated puppy, or a puppy that has only had their first injection, doesn’t have any protection against parvovirus or the other diseases we vaccinate against. Your puppy will be safe to go out for a walk and meet other dogs 1-2 weeks after they complete their first vaccination course, until then:

  • Home and garden. Your puppy is safe to go into your garden as long as no unvaccinated dogs have visited recently.
  • Public places. You can take your puppy out into public but make sure you carry them and don’t put them down onto the ground
  • Puppy classes. As long as your puppy is healthy, it’s okay to enrol them in a puppy class. The benefits far outweigh the very small risk of catching parvovirus from another puppy.
Published: April 2020

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Written by vets and vet nurses. This advice is for UK pets only.

Illustrations by Samantha Elmhurst