Parvovirus (Parvoviral Enteritis or "Parvo," for short) is a virus causing severe infection in puppies and dogs. It invades and destroys rapidly growing cells in the intestine, bone marrow and lymphoid tissue resulting in nausea, vomiting and severe hemorrhagic (bloody) diarrhea. The invasion of the bone marrow cells causes a decrease in the white blood cell count leading to increased susceptibility to bacterial infections and sometimes to a shock-like condition called endotoxemia. The disease can vary from mild to fatal if not properly treated.

Parvovirus is extremely contagious to other dogs. Infection is generally attributed to ingestion of material contaminated by dog feces and can occur when a dog smells or licks the ground. Direct contact with another dog is not necessary for infection. Parvovirus is shed in the feces of infected dogs for approximately two weeks after initial ingestion and can live in the environment for years. The virus is species specific and is not contagious to cat or humans.

Dogs at highest risk for infection are unvaccinated puppies or those who have not yet completed their vaccine series. It is most common in dogs less than 8 months old. Especially susceptible breeds include Doberman pinschers, Rottweilers, German shepherd, Staffordshire terriers, black Labrador retrievers, and dachshunds. Dogs of all ages can be infected, but puppies and younger dogs are most susceptible. Intact male dogs may also be susceptible for unknown reasons.

Unsanitary and/or overcrowded kennels may increase chance of infection and concurrent infection with parasites, other bacteria or viruses may also increase susceptibility to infection. Proper vaccination of your pet can best prevent the disease.

Parvovirus is an acute and serious disease, not a chronic condition. Virtually all cases need proper diagnosis and hospitalization. If your pet is having active symptoms, it is important to see your veterinarian. Parvovirus can be fatal if not properly treated.