Parvovirus in Dogs
Puppy or unvaccinated dog vomiting, with bloody diarrhoea, lethargy or not eating? Phone your vet now, and say you are worried about parvovirus so they can keep your dog away from other patients. Find an emergency vet
Quick answer
Canine parvovirus is a highly contagious disease that attacks the gut and white blood cells, and in puppies can damage the heart. The AVMA lists lethargy, loss of appetite, vomiting, severe and often bloody diarrhoea, belly pain and fever or low temperature as signs, and says to contact your vet immediately. Puppies of about 6 to 20 weeks and unvaccinated dogs are most at risk. Vaccination starts at 6 to 8 weeks.
From the American Veterinary Medical Association. Not veterinary or financial advice. Worried about your pet now?
On this page (7 sections)
What it is and how it spreads
The AVMA describes parvo as a highly contagious disease caused by canine parvovirus type 2. It spreads through direct contact with infected dogs, their faeces, or contaminated things such as kennels, bowls, leads, and the hands and clothes of people who have handled an infected dog. The virus resists heat, cold, humidity and drying, survives in the environment for long periods, and even trace amounts of faeces can carry it. Source: AVMA, Canine parvovirus.
Symptoms
- Lethargy and loss of appetite
- Vomiting
- Severe, often bloody, diarrhoea
- Belly pain and bloating
- Fever or a low body temperature
- Drooling
The AVMA says to contact your vet immediately if you see these signs. Source: AVMA, Canine parvovirus.
Which dogs are most at risk
All dogs can catch it. The AVMA lists puppies of about 6 to 20 weeks, unvaccinated or incompletely vaccinated dogs, and some breeds, including Rottweilers, Doberman Pinschers, bull terrier breeds, German Shepherds and English Springer Spaniels, as at higher risk. See our Dobermann, Rottweiler and German Shepherd guides. Source: AVMA, Canine parvovirus.
At the vet
The AVMA says diagnosis is usually confirmed with a faecal test, and that severe cases need immediate, intensive treatment and round-the-clock monitoring, often with several days in hospital. Prompt, intensive treatment improves a dog's chance of survival. Phone ahead: the practice will want to keep your dog away from other patients. Source: AVMA, Canine parvovirus.
Vaccination and prevention
Parvovirus is part of the core combination vaccine recommended for all dogs. The AVMA says puppies start the series at 6 to 8 weeks, with the final dose usually at 16 weeks or older, a booster within a year of the last puppy dose, then generally every three years. Unvaccinated or overdue adults can still be vaccinated. Until a puppy has finished its course, take care where dogs gather (parks, classes, day care, kennels, groomers), keep it away from other dogs' faeces, and keep a sick dog away from other dogs, including those at home. Source: AVMA, Canine parvovirus. More: puppy vaccination schedule.
Questions people ask
What are the first signs of parvo in a dog?
The AVMA lists lethargy, loss of appetite, vomiting, severe and often bloody diarrhoea, belly pain and bloating, fever or low body temperature, and drooling. Contact your vet immediately.
Which dogs get parvo?
All dogs can. The AVMA says puppies of about 6 to 20 weeks and unvaccinated or incompletely vaccinated dogs are most at risk, along with some breeds such as Rottweilers, Doberman Pinschers and German Shepherds.
When should puppies be vaccinated against parvo?
The AVMA says the series starts at 6 to 8 weeks, with the final dose usually at 16 weeks or older, a booster within a year, then generally every three years. Your vet may adjust this.
How long does parvovirus survive in the environment?
The AVMA says the virus resists heat, cold, humidity and drying and can survive in the environment for long periods; even traces of faeces can carry it.
Sources
- AVMA, Canine parvovirus, read 9 November 2026.
Related pages
Puppy vaccination schedule, dog vomiting, dog diarrhoea and pet emergency: what to do now.