Parvovirus and Puppies
Spring is in full swing and summer is just around the corner, and so is parvo season. While it occurs all year round it is much worse in the warmer months. Parvo virus mostly affects puppies and young unvaccinated dogs. Since there are so many new strains that have mutated over the years even older dogs can get it. The virus showed up the 70’s and has spread worldwide since then. The way the virus is constructed makes it very hardy so it can live in almost any environment for a very long time. The virus is shed in great numbers by infected dogs (some of which do not show symptoms) so parvo is always being put back into the environment and it is EVERYWHERE. This means that parvo is in your house, it’s in your yard, it’s at the grocery store, and on the bottom of your shoes. You can try and disinfect the environment to decrease its numbers but you can never completely get rid of it.
Puppies are especially prone to parvo virus because their immune systems are still developing and they have had no previous exposure. Older dogs are less susceptible because at some point they have been exposed to it and their immune system have had a chance to react. Hopefully though they have been vaccinated for parvo so they will not get sick when they do encounter the virus. When a puppy is born they get colostrum from the mother’s milk. If the puppy was not a good nurser or if did not get mother’s milk after it was first born it is more susceptible to infection. The colostrum helps protect the puppies from viruses for a time but as the mother’s antibodies start to decline the puppy is now vulnerable to viruses. This is why we don’t start vaccines until they are 6-8 weeks old because their mother’s antibodies are still protecting them. Puppies need to start their vaccines at this age to help their immune system recognize and be able to mount a response against parvo. Until they have all boosters at 3-4 week intervals until they are 16-18 weeks old they can still get parvo and get very sick. Black and tan colored breeds are more susceptible to the virus and may require an additional booster to keep them protected.
Once the virus is in the body it attacks rapidly dividing cells like the lining of the intestine, bone marrow, and lymph cells. This means that the lining of the intestines are broken down causing anorexia, lethargy, vomiting, and diarrhea (usually with blood in it). As the lining of the intestines break down it allows the bacteria that normally lives in the intestine to get into the bloodstream and cause what is called sepsis. Sepsis will kill the puppy. The other part of the equation is the destruction of white blood cells; these cells help fight off infection so now the puppy has this nasty virus that is not only destroying it’s GI tract but it is killing the very cells that help fight off infection. Treatment is long and expensive and there is no guarantee that it will work. There is no medication that kills the virus so treatment is aimed at supporting their body while it slowly fights off the infection.
It is so much easier and cheaper to try and prevent an infection than treat it. While they are never 100% protected until they have had all their vaccines at the correct intervals, you can do a few things to decrease the chance of getting parvo. The first thing you can do is pick a puppy from a reputable breeder and not purchase one from a puppy mill or pet store. I can’t tell you how many people impulse by a puppy in a Walmart parking lot or pet store only to bring it home and it is sick. You should go see the environment that the puppy has been brought up in and see if the parents and the puppies, if old enough, have been vaccinated. If they cannot produce records from a veterinarian and there are multiple dogs and puppies running around in a dirty environment walk away! Some breeders will buy their own vaccines but if the vaccine has not been properly handled and kept at the right temperature it will not work.
Another great way to keep exposure to a minimum is to not take your puppy anywhere until it has had all of its vaccines. That means no fun trip to the pet supermarket or to the dog park. These places are hot beds of virus and you are just asking for it if you are taking your puppy out in public before they are fully vaccinated. Keep the puppy at home and don’t let other people bring dogs to your house unless they are fully vaccinated. It is also a good idea to make sure that all dogs that are in the household are fully vaccinated before any new dogs or puppies are introduced.
As with most things in life, a little preparation and education about what you are getting yourself into can prevent a very costly and deadly problem. If you are thinking about getting a new dog make sure you have familiarized yourself with the breed and with possible health problems. Any veterinarian worth their salt will be more than happy to sit down with you and educate you on what needs to be done and why. Then hopefully getting a new puppy will be a happy experience and not an expensive and even sad story that ends before it got a chance to begin.
M. H. Archer, DVM