Balancing Parvo Risk and the Need for Socialization in Young Puppies

Balancing the risk of your puppy contracting Parvo virus against the need for socialization of your puppy, and the effort it takes to sequester your puppy until the age of 16 weeks, is no small decision. In this article I will provide a brief overview of what Parvo is, what makes it so dangerous, and the actual costs of treating a puppy that contracts Parvo.

First, a bit about our enemy, properly called Canine Parvo virus. This virus was unknown until the late 1970's, when it began appearing in, and devastating, the canine population. There is now a vaccine that produces immunity to the virus in adult dogs, and deaths due to Parvo now occur almost exclusively in puppies. The symptoms of Parvo infection are lethargy,vomiting and diarrhea. An infected dog sheds the virus in its vomit and diarrhea, and a susceptible puppy will be infected if it ingests even a tiny amount of those bodily fluids by sniffing or licking a surface that contain them. Some dogs will get what is called a 'subclinical infection'. They will not appear particularly ill, but will shed large numbers of viruses in their stool nonetheless, and thus contaminate the environment.

What makes puppies so vulnerable to Parvo? For one thing, if they DO contract the virus, the virus causes vomiting and diarrhea. Because of their small size they dehydrate quickly, and dehydration leads to shock, organ failure and death. The virus also destroys the lining of the intestines, allowing bacteria from the intestines to leak into the rest of the body, causing a fatal infection called septicemia.

During the time puppies are nursing, and for a period of time afterwards, they have antibodies to Parvo virus that they received from their mom's milk. Interestingly enough, it is mom's antibodies, circulating in a puppy's blood, that will destroy any Parvo vaccine administered to the puppy, as well as any Parvo virus to which they are
exposed. This is the reason puppies are vaccinated multiple times between 6 and 16 weeks of age. Without doing an expensive blood test on a puppy, it is impossible to know if mom's antibodies are still circulating, ready to destroy any invader, including the vaccine. Since one does not know EXACTLY when mom's antibodies are completely gone, vaccinations are given at 4 week intervals between the ages of 5 or 6 weeks and 16 weeks. There is a greater than 90% chance that, by the last vaccination at 16 weeks, the mom's antibodies are gone and the vaccine will cause a pup to manufacture antibodies of its own. Until then, there is the chance that the pup will be experiencing a window where mom's antibodies are gone, but the pup has not had a chance to make its own. Puppies need to be vaccinated during this window, after mom's antibodies are gone. Once that happens it takes about a week for the puppy to have produced enough antibodies to be immune to the virus. So the safest thing to do is to wait one week BEYOND the final vaccination at 16 weeks to allow your puppy exposure to areas that have a higher likelihood of contamination.

Parvo is considered ubiquitous in the environment. It is extremely hardy, and can live for up to 6 months even in freezing or blistering temperatures. Any area where dogs have been in the last 6 months is considered potentially contaminated unless it has been sterilized with bleach. A dog with Parvo will shed the virus in its stools in the astoundingly large number of 35 million viruses per OUNCE of stool. In addition, it is VERY contagious. It takes approximately 1000 viruses to cause an infection in a dog without immunity. The combination of its hardiness in the environment, the large numbers deposited in the environment, and the low number required for infection, make it extremely easy to contract. Once contracted, it is very dangerous. The death rate, without treatment, for puppies contracting Parvo virus is 35-65%. With treatment, 80% of puppies survive.

What this means for owners of puppies under the age of 16 weeks is that they need to seriously restrict the contact that their puppy has with the environment if they wish to avoid exposure. Not only are outside walks in any place frequented by dogs discouraged, but it means limiting exposure by not allowing visitors who have frequented such places. Parvo can be carried on clothing, shoes and car tires. Walking through a mall parking lot that has a pet store brings the risk of carrying the virus into your home on your shoes. Many new puppy owners begin a policy of 'No Shoes in the House' for this reason.

The next obvious question becomes, if treatment for Parvo is relatively successful, then might not it be reasonable to risk exposure and just treat it if it occurs? While that is a possible choice, one should be clearly aware of the expenses before making it. The blood test that will diagnose Parvo costs between $65 and $100. Once diagnosed, a puppy that contracts Parvo requires intensive care treatment in a veterinarian's office. A minimum of a 3-5 day hospital stay is usually required. More blood tests will be required to determine if the Parvo has caused the bone marrow to stop producing white blood cells, and to determine if the puppy's blood proteins are too low, which can cause fluid in the lungs. If either of those occur, special transfusions are required to save the pup. The pup must receive medications to slow the diarrhea, medications to stop the nausea and vomiting, and medications to kill the bacteria that cause the septicemia. They also require fluids supplied intravenously, as dehydration is one of the major causes of death. All told, the lowest cost one generally sees for a successful Parvo treatment is in the range of $850-$1000. Bills up to $3000 are not unusual.

Finally, owners must be aware that vaccines are not effective 100% of the time, and certain breeds (German Shephards, Rottweilers and Dobermans) seem more susceptible to Parvo infection. Sometimes even a properly vaccinated dog will contract Parvo virus. All owners should learn to recognize the symptoms of Parvo (high fever and lethargy, followed by vomiting and bloody diarrhea) and seek veterinary attention immediately if they see them in their dog.