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August 18, 2009

Parvo Virus

In the past month or so, we have treated several cases of puppy parvo in the clinic. It seems that we cannot stress enough how important it is to get your puppy or dog properly vaccinated against parvo virus. This very common disease can quickly turn a happy, healthy dog into a sick or dead dog in just a few hours to days. The virus and disease is described well at the following site: {Canine_parvovirus} Usually, the first signs we see with parvo viral infection can easily be mistaken for a simple upset gastrointestinal tract --a little vomiting and the dog no longer wanting to play. This is usually followed in a day or two by diarrhea, and then bloody diarrhea. Unless the dog is treated quickly, death from dehydration and electrolyte imbalance can occur quickly.

Parvo virus is everywhere, and I mean EVERYWHERE. It is a very sturdy virus -- only reliably killed with a strong bleach solution. It can last in the ground or on other surfaces for years. You never know where your puppy may come in contact with it, and of course puppies are always sniffing, licking, chewing anything they can find. Take your unvaccinated puppy to a friend's house where several years ago another dog have parvo diarrhea all over the yard and unbeknownst to you, you just infected your puppy with parvo.

It is the saddest thing when a puppy comes in and is deathly ill with parvo. Sad because in most cases, the illness and possible death could have been avoided if the owner had been correctly informed about vaccination. Often the owner is mistaken told by a breeder that the 6-8 week old puppy has been vaccinated twice already and needs no further vaccination. Or, the owner mistakenly assumes that since the puppy has been vaccinated at least once by the breeder, then it is up-to-date. This is just not true.

How the vaccination works is a little complicated, so hang in with me. Puppies are born with some maternal antibodies already running around in their blood, and then they receive more antibody protection through the colostrum they nurse from the mother dog in the first 24hrs post birth. This maternal antibody protection, against myriads of diseases, lasts anywhere from 6-10 weeks of age depending on many factors. A vaccine stimulates the body to make their own antibodies (not passive antibodies from the mother) and memory to make more antibodies when challenged by a virus or bacteria. So, for the vaccine to work, there must be very little of the maternal antibodies left in the puppy, and as the age for this varies greatly from puppy to puppy -- we are stuck doing sort of a crap shoot when it comes to vaccinating puppies. To try to make sure that every puppy is adequately vaccinated, we need to cover both ends of the spectrum. Some puppies may run out of maternal antibody by 6-7 weeks while others will still be protected until 10-11 weeks. accomplish this at 8-10 weeks. And since most vaccines need at least two doses to be fully effective, we need to start vaccinating around 6-8 weeks and continue with boosters every 3-4 weeks until 14-16 weeks. So, there it is-- it all comes down to immunology -- not money sucking veterinarians trying to make a buck. We especially don't like to see sick and dying puppies in the clinic when we know it could have been prevented.

A couple more thoughts on parvo. It makes me cringe to see young puppies taken out and about to parks, the river, and other public places. Knowing what you now know about parvo and immunology, it should make you cringe too. You really shouldn't feel safe taking a young puppy to a public area until it has had at least 2 (or better yet 3) vaccinations for parvo. Also, just because you have an old dog, don't think that you don't have to worry about parvo any longer. An old dog that has not been vaccinated in a few years can be just as susceptible to parvo as a young unvaccinated puppy -- an aging body and other illnesses can make the immune system not as strong. Oh, and one more thing -- we recommend getting your vaccines from your veterinarian because you just don't know how the vaccines from the catalogues or feed store have been handled and stored. Vaccines are temperature sensitive and cannot be sure they have been kept cool. Our vaccines come on ice overnight from sources we trust -- if they are warm, we send them back. No sense taking risks.

A couple of good sites to visit about parvo: