Canine Parvovirus Recovery and Environmental Decontamination
Allegheny Veterinary Services


Your pet is recovering from extensive damage to the intestinal tract. It is typical for stool to be a little loose at first or for no stool to be produced for a few days as the tract recovers. The stool should gradually firm up over the first 3 to 5 days at home.

Your pet may resume normal activity and attitude over the first week at home. If diarrhea persists, vomiting occurs, or your pet seems depressed, please contact our office at once for further instructions.

Your pet may be ravenously hungry after going so long without food. Do not allow him to gorge as this can result in further vomiting or diarrhea. Feed smaller meals separated by at least an hour or two.

• Feed the therapeutic diet we have provided for the first few days at home. Then resume the normal diet. Do not feed table scraps. Stick to the diet recommended by your veterinarian.


Your pet should be considered contagious to other puppies for at least 6 weeks. Therefore, trips to the park, obedience school, or visiting other neighborhood areas where pets comingle, should be avoided during this time. If your pet is less than 16 weeks of age, he should not be allowed in public areas until the vaccination series is fully completed. He can be considered immune to parvovirus after recovery. However, puppy vaccinations include many other infectious diseases for which your pet needs to be vaccinated against.

Other Pets

Humans are not susceptible to canine parvovirus infection, though some strains can be contagious to cats. Adult dogs that have been vaccinated are not susceptible either. Introducing new puppies poses a problem as the parvovirus persists a long time in the environment. When in doubt, make the new puppy an older individual (16 weeks or so) who has already completed his/her vaccination series. Any obviously contaminated material should be removed (fecal- or vomit-contaminated objects that cannot be bleached, any remaining areas of feces, etc.). See section below on Decontamination of the Environment.


Your pet may be bathed any time as long as you do not allow him to get cold or chilled after the bath. Bathing will reduce the amount of virus left on his fur and will help reduce contagion.

Resuming Vaccines

Your pet cannot be re-infected with this virus for at least 3 years and is probably protected for life after surviving infection. However, it is imperative that he still receives vaccinations as there are other viruses that he should be protected against.

Your pet should lead a normal life once the recovery period is completed (1-2 weeks). In rare cases, there may be lasting effects on the heart.

Disinfecting the Environment

Canine parvovirus is especially hardy in the environment and particularly difficult to remove. It is readily carried on shoes or clothing to new areas (which accounts for its rapid worldwide spread shortly after its original appearance). It is able to overwinter freezing temperatures in the ground outdoors, plus many household disinfectants are not capable of killing it indoors.

• Infected dogs shed virus (in their stool) in gigantic amounts during the 7 to 10 days following exposure. Because such enormous amounts of virus are shed, there is a HUGE potential for environmental contamination when an infected dog has been there.
• It is important to realize that because the canine parvovirus is so hardy in the environment, it is considered ubiquitous. This means that no environment is free from this virus unless it is regularly disinfected.
• A parvoviral infection can be picked up anywhere, although it is easier to pick up an infection in an area where an infected dog has been simply because of the larger amounts of virus in a contaminated area.
• Whether an individual dog gets infected or not depends on the number of viral particles the dog experiences, what kind of immune experience the dog has had with the virus before (vaccinated? previously infected? How much past exposure?), and how strong the individual dog is (stress factors, diet, etc.)

A typical/average infectious dose for an unvaccinated dog is 1,000 viral particles. For some dogs far less is needed. For other dogs, far more is needed. An infected dog sheds 35 million viral particles (35,000 TIMES the typical infectious dose) per OUNCE of stool.

Environmental Decontamination

Parvovirus is virtually impossible to completely remove from an environment. The goal of decontamination is to reduce the number of viral particles to an acceptable level. There are many cleaners on the market with claims to eliminate parvovirus. However, realistically it is virtually impossible to remove parvovirus from an environment.

Bleach: One of the best and most effective disinfectants against parvovirus is BLEACH. However, it important to note that bleach is inactivated in the presence of organic material such as feces, vomitus or other bodily fluids. Therefore, all surfaces and items must first be cleaned with a detergent or other household cleaner. Then, mix one part bleach with 30 parts water. This solution is then applied to bowls, floors, surfaces, toys, bedding, and anything contaminated that is colorfast or for which color changes are not important. The bleach solution must be allowed to soak on the surfaces and items for at least 10 minutes to be effective at killing the virus. Disinfection becomes problematic for non-bleachable surfaces such as carpet or lawn.

Steam Cleaning: Steam is also able to kill the virus.

Rescue® (accelerated hydrogen peroxide cleaner): This is a virucidal agent that we use in our hospital. It is safe on all surfaces and effective as a detergent and disinfectant. Gallons of this cleaner can be purchased if you prefer this over bleach.

Indoor Decontamination

Indoors, where normal room temperature is maintained, the virus loses its infectivity within one month. Therefore, it should be safe to introduce a new puppy indoors one month after the active infection has ended.

Outdoor Decontamination

Freezing does NOT kill the virus. If the outdoors is contaminated and is frozen, you must wait for it to thaw out and warm up before safely introducing a new puppy. Shaded areas should be considered contaminated for seven months. Areas with good sunlight exposure should be considered contaminated for five months.

If you have any questions about your pet’s care after discharge from the hospital, please feel free to contact our office.