The little 3 month old Shepherd mix puppy was flat on the table with a fever of 105 degrees. Just yesterday he had been playing and acting like a normal puppy, but in the evening he had started vomiting, and this morning he had started with some red-tinged, liquid diarrhea. He wouldn’t eat, he wouldn’t play, he wouldn’t even lift his head off the floor. His owner had just taken him in as a favor to a cousin who had gotten the dog and had done his best to hide it. Inevitably the dog was discovered by his landlord who reminded the cousin in no uncertain terms that the no pets rule in the apartments meant he had to get rid of the dog or move out. With all the cloak and dagger activity during the past few weeks the puppy had not yet been to a veterinarian for anything. A quick test confirmed that the source of the problem in the puppy was a parvovirus infection, or "parvo".

Parvo is a ubiquitous viral disease that attacks the lining of the intestines. Marauding virus particles enter each cell and multiply until the cell explodes and unleashes a horde of new virus particles that then go out an look for more cells to pillage. In a short period of time the once pink and happy lining of the intestines is left in bloody, shredded tatters. Fluid and blood come rushing out the back end in the form of diarrhea, and the lining of the stomach becomes so ravaged that continual vomiting occurs. The host of bacteria that normally live quite happily minding their own business inside the intestines suddenly have a direct route into the bloodstream, where rather than minding their own business they can cause secondary infections everywhere and general systemic collapse. The immune system rushes to the crime scene to try to stop the damage, but often gets completely expended before the job is finished and the reserves may take days to get there to help. Most untreated dogs will die an agonizing death over the course of about a week.

If you have gotten a new puppy and you are on the fence about whether or not all the bother and expense of that first series of vaccines at 8 weeks, 12, weeks, and 16 weeks of age is really worth it, take a moment to think about the fact that parvo is so prevalent in the environment that the question is really not "if" an unvaccinated puppy will get parvo, it is "when" Any dog that has not been vaccinated can get parvo, but the highest percentage of cases occur in dogs between the ages of 6 weeks and 20 weeks, and some breeds like Rotweillers and Pit Bulls seem especially susceptible Fortunately for our dogs, current vaccines are so effective that it is almost unheard of for a dog who has been properly vaccinated to become sick with parvo, even when directly exposed to an actively infected patient. At the time you get that new puppy you have the ability to choose which route your puppy’s health will take.

For those that, for whatever reason, find themselves with a dog with parvo, we can usually, although not always, save a patient if aggressive measures are taken to provide appropriate supportive care and hospitalization. Because parvo is a viral disease there is not really any medication that directly knocks out the virus, although there is some possibility that Tamiflu, the anti-influenza medication used in people may have some benefit when started early in the course of the disease. The main part of the treatment is aimed at preventing the patient from dying from dehydration and opportunistic bacterial infections before the immune system can gather its forces together enough to defeat the virus. Most patients need IV fluids with some sugar and potassium, IV antibiotics to stop any intestinal bacteria that want to sneak into the bloodstream, and anti-vomiting medication to relieve some of the misery. A usual course of treatment takes anywhere from 2-7 days in the hospital. The prognosis for complete recovery with no lingering health effects is pretty good with aggressive care, although some dogs are so severely affected that nothing we do is enough to save them. Every now and then I hear of a case that survived without hospitalization, but those are the very lucky ones, and they are not common.

It is not often that we get such a simple choice regarding our pet’s health: either choose not to vaccinate and allow the dog to become infected with parvo, or vaccinate and prevent a terrible disease. It seems like the right answer is not hard to come by.