Parvo Infections

Parvo Infections

Q. What is Parvo and is it deadly?


A. Parvo is a viral disease, first seen in the United States in 1978. It affects the gastrointestinal track, but in rare occasions can cause a heart condition called myocarditis. The disease is usually seen in puppies and unvaccinated dogs. The virus is easily spread from an infected dog to another by people and the environment. Besides being spread from dog to dog, some wildlife such as raccoons, coyotes, wolves, fox, mink and bobcats can spread the virus. 

The Parvo virus is very resilient. It can last a long time in the environment and is resistant to heat, cold, humid, and dry conditions. Infected feces is the main cause of spread. Dogs with the virus can infect another with direct contact by their fur and feet, from people who handle the sick dog, and even on your shoes without handling the dog, in kennels on leashes, collars, bowls, and toys. 

The signs of Parvo are lethargy, inappetence, fever, or abnormally low temperature, vomiting, diarrhea that usually is bloody and smells bad, abdominal pain, bloating, and anemia. The vomiting and diarrhea are usually severe and causes dehydration. The virus infection causes damage to the intestines and the immune system which can lead to septic shock. 

Puppies under the age of four months are the hardest hit with this disease. Usually, puppies get antibodies when they are born from the mother’s milk. These antibodies are in the milk the puppies drink during the first few days. If a mother has adequate antibodies against Parvo, the puppies will benefit with passive immunity. These antibodies have a life span of months, but if the puppy is challenged, the antibodies get used up. For various reasons, not all the pups in the litter get the same amount of antibodies. Older puppies and dogs can get sick if they don’t have enough immunity. 

Most deaths occur in the first 48 to 72 hours, so seeking veterinary care at the first signs of illness is necessary. 90% of sick dogs will recover with treatment. 

Diagnosis of this disease is determined by history, symptoms, physical exam, and a fecal test for the virus. Laboratory tests will be done to assess the severity of the disease and any complications that may be present. There isn’t a drug to kill the virus. Treatment is supporting the immune system with fluids, electrolytes, proteins, making sure to keep him warm, administering medicine to stop the diarrhea, vomiting, pain and prevent secondary infections. This supportive care is continued until the pup’s immune system can take over. 

Treating Parvo can be intense, take a long time, and is expensive. Even with the best of care the dog may die. 

Prevention is the key. Appropriately vaccinate your dog against the disease. You can follow up with antibody titers to assess how well your dog is protected. There are some dogs who will not respond to a vaccine and will not be protected no matter how often they get vaccinated. This is rare. Prevent your pup from licking feces on your walks. Keeping yards, kennels, crates, and your dog’s bowls, leashes, collars, and such clean are a big part in keeping him safe.


Judith K. Herman DVM, CVH

Animal Wellness Center

Augusta, Maine


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