Parvo is a term we throw around when talking about dogs, especially when they are puppies. However, when I ask people if they know what it is, many times they will answer, “No.” So why does your veterinarian give your puppy and adult dog a parvo shot? Simply put, the vaccine is the dog’s best defense against a virus that can be very deadly.

The parvovirus is a virus that has been around for quite some time and was extremely difficult to treat when it first began to infect dogs. Interestingly the virus is believed to have arisen from a parvovirus common in cats. Veterinarians began treating dogs of all ages for vomiting and bloody diarrhea, and many were dying when the disease first emerged. However, it now affects puppies and unvaccinated adults, and even those that become ill have a very good prognosis if treated.

How does the virus behave in animals? The virus is shed in the feces of a dog that is infected, and the dog does not have to be exhibiting signs to shed the virus. When a naïve dog investigates the stool from an infected dog, they inhale the virus and it is then swallowed. The environment can also be contaminated for a long time. The stool does not have to be present to infect the dog. Investigating an area that has been contaminated in the past is enough to infect a dog. The virus, once it is in the dog, will attack rapidly dividing cells, such as the lining of the intestines and embryonic cells if the dog is pregnant. This of course leads to the vomiting and bloody diarrhea that people associate with parvo. Infection with the parvo virus will also lead to neutropenia. Basically, there is not enough of a particular white blood cell to fight off bacteria. This will lead to secondary bacterial infections and sepsis. The chronic vomiting and diarrhea can lead to dehydration and low blood sugar. When all of this is combined together you get an extremely sick dog. As a side note, to date there have been no cases of human infection with the canine parvovirus.

Now that we have a sick patient, what is the next step? There are several things that need to be done to help the sick patient. The most important step is correcting the dehydration. When a pet is dehydrated all of the organs are stressed, the electrolytes are out of balance, and the body cannot function efficiently. Correcting the dehydration can be done in the hospital or as an outpatient procedure. This is, however, at the discretion of the veterinarian and based on the patient. Some veterinarians will begin therapy with Tamiflu©. Yes, this is the medication given to humans suffering from the flu but it also has antiviral actions against the parvovirus. This treatment can be expensive and during certain times of the year it can be difficult to obtain. In addition to correcting the dehydration, antibiotics and anti-nausea medication is given. Remember the word neutropenia, the drop in a particular white blood cell? The antibiotics are to treat any secondary infections due to the neutropenia. The antibiotics do not treat the virus; the animal’s body has to do that. Once you can nurse the pet through the vomiting and dehydration, they are generally on their way to recovery. During this time you are bleaching everything possible to reduce the virus in your environment. Bleach is one of the best ways to kill the virus in the house and on objects. It is, unfortunately, very difficult to treat your yard in this manner and I wouldn’t recommend it.

The parvo virus sounds pretty nasty so how do you keep your dog from becoming infected? The answer is simple, vaccines. Notice I said vaccines, meaning more than one. Veterinarians often hear that the puppy can’t have parvo because they had a shot at six weeks old. That is a great start but they need to be boostered every two to four weeks according to the schedule given by your veterinarian. This is especially true if another dog in the environment had been sick with parvo. With proper vaccination this is an extremely preventable disease of dogs.

Do we have parvo in this area? That is a definite yes. With that in mind, don’t forget to vaccinate your puppies starting at six weeks of age. You and your veterinarian will discuss how many vaccines will be given and how often. Keep them healthy so you can enjoy their time as puppies versus having to nurse them through a very serious infection, or possibly lose them entirely.