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Canine parvovirus infection in dogs

Canine parvovirus (CPV) is a highly infectious viral disease that can be fatal to dogs. Puppies between the ages of six weeks and six months, and unvaccinated dogs, are most at risk. Our vet advises how to prevent parvovirus in this article.

This article was written by a FirstVet vet


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What is parvovirus?

Parvovirus is a virus that affects rapidly dividing cells such as the intestinal cells lining the gut wall, lymph node cells and bone marrow.

How does my dog get parvovirus?

Parvovirus can be contracted through contact with faeces from infected dogs usually via the environment or form contaminated shoes/clothing and unwashed hands. Virus particles are resistant to most cleaning products and weather changes, and can survive in the environment for up to one year. Parvovirus is more commonly seen in urban areas where there is a higher density of unvaccinated dogs, but can occur anywhere.

What are the symptoms of parvovirus?

Parvovirus infection is a very serious illness, particularly in puppies. After catching the virus it takes up to seven days for signs to be seen. Canine parvovirus can manifest in two different ways. The more common form is the intestinal form. This is characterised in dogs by vomiting, diarrhoea, weight loss and lack of appetite (anorexia). The virus attacks the cells that line the dogs intestine, which stops them being able to absorb nutrients. This causes severe diarrhoea and leads to weakness and dehydration. The less common form is the cardiac form. The virus attacks the heart muscles of unborn foetuses and very young puppies, often leading to death.The virus also attacks lymphoid tissue and bone marrow which produce immune cells and can lead to poor immune system.

The most common signs are:

  • Profuse, foul smelling diarrhoea, often containing blood

  • Loss of appetite and vomiting

  • Fever, lethargy and depressed demeanour

  • Painful abdomen

  • Severe weight loss

  • Sudden death

The infection may lead to shock. Shock is a sudden drop in blood flow, either through a loss of fluids as a result of profuse diarrhoea, or from sepsis (an extreme immune response to the infection).

Signs of shock

  • rapid breathing

  • cold extremities

  • inability to rise or interact, floppy and/or unconscious

How can I protect my dog from parvovirus?

  • Vaccination in puppies and dogs is key to prevention, and parvovirus vaccination is included in a routine protocol used by vets in the UK

  • All puppies should receive two vaccinations (sometimes called ‘puppy shots’), two weeks apart, between 6 and 16 weeks old

  • All dogs should receive an annual booster vaccination

  • Your dog’s vaccination record must be signed and dated by a veterinary surgeon or registered veterinary nurse (RVN) in order to be valid

  • Puppies are most susceptible to parvovirus. Ensuring that hygiene measures are in place and that the puppy’s mother is vaccinated can help to prevent the disease

  • Do not allow unvaccinated dogs and particularly puppies to be exposed to the virus by not putting them down or walking them in public places, particularly where people and dogs congregate, like parks

  • Rottweilers, Labradors, Doberman Pinschers, German Shepherds, English Springer Spaniels and Alaskan sled dogs are particularly susceptible to the virus - we do not yet know why

Can vaccinated dogs get parvovirus?

There are a small number of dogs who will not respond to the vaccine and may not be immune to the disease. You can discuss checking your dog’s immune status with your vet, especially if they are in a high risk environment.

How is parvovirus treated?

Unfortunately, there is no specific treatment for parvovirus and supportive care to help overcome the symptoms of parvovirus is the mainstay of treatment. This includes fluid therapy, pain relief, and treatment for secondary infection.

Treatment is often expensive, lengthy and can affect your dog’s immune system for some time meaning they are at risk from other infections. They can remain infectious for up to two months, so it is important to isolate them from other dogs and ensure dogs in contact are fully vaccinated.

Sadly, parvovirus has a mortality rate of over 90% in cases that are left untreated and puppies are particularly at risk of death as they have less developed immune systems. Prompt treatment will reduce the risk of death, and therefore you must visit your vet without delay if your dog or puppy is displaying any of the above symptoms, particularly if they are not fully vaccinated.

Remember: Vaccination of your dog and puppy against parvovirus is KEY in preventing infection and this is much better than attempting treatment which is rarely successful.

How can I disinfect the environment after parvovirus?

Parvovirus is extremely hardy and resistant to most cleaning products. It is impossible to completely remove all particles from the environment so the aim is to reduce the number of particles to an acceptable level. Infected dogs should be isolated to prevent widespread contamination.

Without any disinfection, the virus should become inactive in approximately one month in indoor environments at room temperature or higher and 5-7 months in outdoor areas with sunlight. Freezing protects the virus and you must wait for outdoor areas to warm up and thaw. However, most people would want to disinfect the environment.

In order to effectively decontaminate your home

  • Pick up and safely dispose of any organic material

  • Clean all indoor areas and objects that may be contaminated with a concentrated bleach solution of 1 part bleach to 30 parts water. This includes water bows, food bowls, bedding and surfaces. Soak the area for 10-15 minutes if possible. Bleach is one of the only products known to kill the virus

  • On surfaces that cannot be bleached e.g. carpets. Steam cleaning can help reduce viral load. Without any disinfectant the virus should be inactive after one month

How to reduce the viral load outside

Hosing down the area multiple times to dilute the concentration of virus particles. Dilution coupled with the UV rays from sunlight will bring the levels down to acceptable levels. Never use bleach outside.

When can I bring a new dog puppy into the home?

We would advise waiting at least 1-5 months before bringing in a new puppy or dog into the home depending on the risk of virus in the environment (see above).

We would recommend making sure your dog or puppy is fully vaccinated and if possible around 16 weeks or older before entering the home.

It may be worth considering a third vaccination in puppies going into a higher risk environment. Your vet will be able to advise if this is necessary,

When to see your physical vet

If you are concerned that your dog or puppy is showing signs of bloody diarrhoea, fever, lethargy especially if they are not fully vaccinated or up to date with their vaccines.

Still worried?

Book a video appointment to have a chat with one of our vets.

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