Ask a Pets Blogger: How Long Does Parvo Live in the Environment?

A friend of mine recently fostered a dog who was suffering from parvo. With vet treatment, the dog survived and has gone on to a forever home… but my friend is now worried about future fosters. What can she do to protect the next dog that comes to stay with her?

Parvo is a tough one to get rid of because it is so hardy — especially outdoors.

A few ways in which the parvovirus can be spread:

  • Carried on shoes or clothing.
  • Surviving sub-freezing temperatures to infect dogs after the spring thaw. Freezing does NOT kill the virus — it actually protects/preserves it.
  • Infected dog shed large amounts of the virus in their stool — especially in the first two weeks after exposure. This can leave large quantities of the virus in the environment.
  • The virus can survive many household cleaners and disinfectants.

Indoors, the virus will lose the ability to infect a dog after about a month. So if you do nothing to disinfect your home, it will be reasonably safe about a month after an active infection has cleared up.

Outdoors, the virus is far hardier. Areas of your yard with good sunlight exposure can be considered contaminated for at least five months; shaded areas can be considered contaminated for at least seven months.

It’s hard — indoors OR out — to completely eliminate the parvovirus. You can make your home safe by reducing virus particles to a safe level. Bleach is considered the best disinfectant against parvovirus. Mix one part bleach with thirty parts water and clean food and water dishes, floors, walls, surfaces, toys, bedding, and anything else that may be contaminated. Since you probably can’t bleach your carpets or upholstery, it may be best to wait a month for the virus to die off before welcoming another pet into your home.

Decontaminating the yard is more problematic. A thorough watering of the lawn can help dilute the virus, but won’t eliminate it. You can spray the lawn with the same bleach and water mixture — this will kill the grass, but also kill the virus.

Vaccination can also help protect future canine fosters or residents against picking up the parvovirus.