Parvovirus in puppies: early signs, treatment, cleaning and prevention

Canine parvovirus is a highly contagious disease of dogs, especially puppies between 6 weeks and 6 months old that have not finished their vaccinations. The virus attacks the lining of the gut and the bone marrow, causing severe vomiting and diarrhoea, rapid dehydration and a weakened immune system. Without treatment it can kill within days, but the chances of survival rise a lot with early treatment at a clinic.

How does parvo spread?

The virus is shed in the faeces of infected dogs, and a tiny amount is enough to infect another dog. It is also extremely hardy and can survive in soil, on floors and on objects for many months.

• Puppies pick it up by sniffing or licking the ground in streets, parks and places where dogs gather.
• Shoes, clothes, hands, bowls and crates can carry it into the home.
• A dog that has recovered can keep shedding the virus in its faeces for a while.

Canine parvovirus does not infect people. Cats have a similar disease, feline panleukopenia, which is prevented by the core cat vaccine.

Early signs

Signs usually appear 3 to 7 days after infection and include:

• marked tiredness and no interest in play;
• loss of appetite or refusing food completely;
• repeated vomiting;
• severe diarrhoea, often with blood and a strong, distinctive smell;
• fever — or, in advanced cases, a low body temperature;
• signs of dehydration: dry gums, sunken eyes, and skin that is slow to fall back when gently pinched.

Diagnosis and treatment

A vet can usually confirm parvo with a quick test on a stool sample, and may run blood tests to judge dehydration and the white blood cell count.

There is no drug that kills the virus itself, so treatment supports the puppy's body until it overcomes the infection. It usually includes:

• intravenous fluids to replace lost water and salts;
• medicines to stop vomiting and ease pain;
• antibiotics to prevent secondary bacterial infection while immunity is low;
• gradual feeding as soon as the puppy can keep food down.

Many puppies need to stay at the clinic for several days. Do not try to treat parvo at home with herbs or oral fluids alone; the condition can get worse very fast.

Cleaning the home and protecting other dogs

Because the virus resists most common household disinfectants, follow these steps after talking to your vet:

1. Keep the sick dog away from other dogs, especially puppies and unvaccinated dogs.
2. Remove faeces and dirt first, then clean surfaces with water and detergent.
3. On surfaces that can take it, use diluted household bleach (about 1 part bleach to 30 parts water), leave it for 10 minutes, then rinse.
4. Wash bedding and fabrics in hot water, and throw away anything that cannot be disinfected.
5. Ventilate well, never mix bleach with other cleaners, and keep animals off surfaces until they are dry.

Before bringing a new puppy into a home where a dog had parvo, ask your vet how long to wait and check the puppy's vaccinations.

Prevention: vaccinate first

• Puppy vaccination usually starts at 6–8 weeks of age and is repeated every 3–4 weeks until at least 16 weeks, followed by a booster your vet will schedule.
• A puppy is not fully protected until the series is complete, so avoid places where unknown dogs gather until your vet says it is safe.
• Your puppy can still play with healthy, vaccinated dogs you know in a clean place — early socialisation matters for behaviour.
• If you have a young puppy, take your shoes off at the door and wash your hands after touching other dogs.
• When buying or adopting a puppy, ask for its vaccination record and check the date of every dose.

See also the core vaccination schedule and what to check before adopting or buying.

Frequently asked questions