Parvovirus is not a rare disease that happens to unlucky people. It is common, it is everywhere in the environment, and it concentrates its damage on puppies between about six weeks and six months, which is precisely when a family has just fallen in love with one.
What it does
The virus attacks the fastest-dividing cells in the body: the lining of the intestine and the bone marrow that produces white blood cells. So the gut stops holding fluid in and stops keeping bacteria out, at the same moment the immune system loses the cells it would fight back with.
That is why puppies die of it. Not of the diarrhoea itself, but of dehydration, of the fall in blood sugar and body temperature that follows, and of bacteria crossing a broken gut wall into the blood.
Nothing available anywhere in the world kills this virus. Treatment buys the puppy time, and its own immune system does the rest.
The signs, in the order they usually come
- Unusually quiet and tired, and off its food, often the day before anything else
- Repeated vomiting, including of water
- Diarrhoea that becomes profuse, often bloody, with a smell owners describe as unlike anything else
- A painful, tucked-up abdomen
- Sunken eyes, tacky gums and skin that stays tented when lifted, all of which mean dehydration
- Cold ears and paws, and collapse, which are late and dangerous signs
What to do if you suspect it
- 1Get to a veterinarian the same day, and telephone first so they can isolate your puppy on arrival rather than walking it through a full waiting room
- 2Take any vaccination record you have, and be exact about which doses were given and when
- 3Keep the puppy warm on the way, since hypothermia is part of what kills them
- 4Do not force food or water into a vomiting puppy, which risks it going into the lungs
- 5Keep it away from every other dog in the house and street from this moment
Treatment means an intravenous drip to replace what is pouring out, anti-sickness medication so the gut can rest, antibiotics for the bacteria crossing the gut wall, glucose and warmth, and careful nursing for several days. It is not cheap, and there are no shortcuts that work. With that care, the majority of puppies survive.
Preventing it, which genuinely works
- Complete the vaccination course to about sixteen weeks, then keep boosters up
- Until a week or two after the final dose, avoid parks, streets and any ground where unknown dogs toilet
- Socialise in safer ways in the meantime: carry the puppy out, and use clean homes and healthy vaccinated dogs
- Do not bring a new puppy into a house where a dog has had parvo without talking to your vet first, since the ground stays infectious for months
- Wash hands and change shoes after handling other dogs, because you carry the virus home on both
If you have a puppy at home now and its course is not finished, that calendar is the single most useful thing you can sort out this week. Our dog vaccination schedule guide sets out the timings, and a quick consultation can confirm where your particular puppy stands and what it still needs.
Common questions
What does parvo look like at the start?
A puppy that goes quiet and stops eating, often a day before anything dramatic. Then vomiting, then profuse diarrhoea that is frequently bloody and has a distinctive foul smell. Deterioration is fast, sometimes over hours rather than days.
Can it be treated at home?
Rarely with success. These puppies die of dehydration and of infection entering the bloodstream through a stripped gut lining, and countering that needs an intravenous drip plus injectable anti-sickness medication and antibiotics. Oral rehydration salts cannot keep pace with the fluid being lost, and a vomiting puppy cannot keep them down.
My puppy had one vaccination. Is it protected?
Not reliably. Antibodies from the mother protect a puppy early on but also block the vaccine from working, and they fade at an age that differs between individuals. That is why the course runs every three to four weeks until about sixteen weeks. The gap between the mother's protection fading and the course finishing is when most puppies catch it.
How long does the virus survive in the house or yard?
Months, and in soil and shade it can persist up to a year. It also resists many ordinary disinfectants. Household bleach diluted about one part in thirty, left in contact for ten minutes, is the practical choice on surfaces that tolerate it.
Can my other dogs or my cat catch it?
Other unvaccinated dogs, yes, very readily. Cats do not catch canine parvovirus, though they have their own related disease, panleukopenia, which their vaccination course covers.