How Soon After Exposure Does a Dog Show Symptoms of Parvo?

Dogs remain contagious for four weeks after recovering from the parvovirus.
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Parvo is a solitary strand of DNA protected by a protein coat. It invades the body of its host, attacks the cells and begins replicating itself. First, it attacks the lymph nodes in the throat and then travels to the bloodstream, bone marrow and intestines. By educating yourself on the symptoms and warning signs of this virus, you can help your pet to get on the road to recovery as soon as possible.

How are Dogs Exposed?

Parvovirus is most commonly spread through dog feces. An infected dog will shed the virus in his feces three to four days after exposure, before he shows any symptoms himself. An ounce of feces from an infected dog contains 30 billion to 35 billion units of the virus. One billion units are enough to trigger infection. If a healthy dog comes into contact with infected feces or vomit, he can contract the disease.

Does Exposure Guarantee Infection?

Parvovirus is so prolific it affects most of the environment, including the air and soil. As a result, most dogs have been exposed at one time or another. Just because a dog is exposed, does not mean he will become ill. Puppies younger than 6 months of age are most susceptible, as their immune systems are not fully developed. The majority of canine victims are younger than a year old, although the virus can affect adult dogs as well. Certain breeds are more prone to the disease, including Doberman pinschers, German shepherds, Labrador retrievers and American Staffordshire terriers.

When Do Symptoms Appear?

If your dog’s immune system contracts parvovirus, symptoms will appear within five to 10 days after exposure. However, some dogs may show symptoms as soon as three days or as long as 12. Onset is rapid and death may occur within days without treatment. Symptoms include lethargy, fever, bloody diarrhea and abdominal discomfort. Oftentimes, diarrhea is so profuse a dog will die from shock induced by swift dehydration. Immediate veterinary care is required to prevent death. Dogs who are treated by a veterinarian have a 70 to 80 percent survival rate. The exception is small, young puppies, Doberman pinschers and rottweilers. Their chances of survival are 30 to 50 percent. The moment you notice severe diarrhea and vomiting in your puppy, rush him to the vet for a parvo test.

How Can Exposure be Minimized?

Isolate infected dogs to keep the virus from spreading to other pets. The parvovirus is extremely hardy and can survive in the environment for six to seven months. Sanitize surfaces such as kennels, floors and bowls with a chlorine bleach solution. Mix one part bleach with nine parts water. Vaccinations can be effective in preventing parvovirus, although there is a slight risk of your puppy contracting the disease from the vaccine. Puppies should be vaccinated between 6 to 8 weeks of age and vaccinated again every two to four weeks until they are 4 months old .