Click here to visit the most complete Maltese site on the WWW

Archived Message

Parvo mystery?

by Denny

Our neighbors Shih Tzu died yesterday after a breif illness. She was only 2 years old. They were very responsible pet owners and never took no chances when it came to veterinarian care. It had died from Parvo. She was fully vaccinated against this. I didn't know that was possible. I thought thats what the annual booster shots are for?? Does anyone know or have had a past experience of their vaccinated dog catching this?


Please bear in mind when reading topics pertaining to health issues, that many of these questions were answered by helpful Maltese owners with no formal education in veterinarian medicine. When in doubt seek a professionals advise.

I'll try to answer your question in so much as I only have personal experience with preventing Canine Parvovirus and none with ever having to deal with it after the fact, fortunately.

There could be numerous reasons why this dog was infected with this virus. Here are a two that would come to my mind.

  1. It could be that your neighbors dog was never in reality fully vaccinated from the beginning. You didn't mention in your post where the dog came from. There are some mendacious breeders that will say a puppy had its first shots according to schedule but in fact they did not. Why? $$$$. Vaccines cost them.-Period. I would advise anyone who got a pup from a breeder they just "happened-acrossed" to ignore what the shot records say all together and have it vaccinated like it never had been, unless of course the records were written by a vet. (Many breeders give their own shots).
  2. There is more than one type of Parvo, several strains have been identified in this country. So, even though your dog is truely fully vaccinated, it still is at risk of contracting a new or mutant strain.


Jay,I've got a question maybe you or someone else can answer about Parvo. I have a friend who owns a big Rottweiler and she has told me that I should always make sure my vet vaccinnates Chilli with a *live* virus shot and and not with a *dead* shot (she didn't say dead but it was sort of the opposite of live).

I know that some vaccinations are comprised of live virus or bacteria. Any ideas what should be done regarding the Parvo shot?Thanks,Wendy P. and Chilli
-Wendy P. & Chilli

The Parvo vaccine we use is *modified live*.They have been modified to no longer cause the diseases they vaccinate against. When given they replicate in the animal and allow the body to form antibodies. Since they can replicate the vaccine contains relatively small amounts of live virus which then increases after vaccination. The other class of *killed vaccines* doesn't do this. The *modified live* gives good immunity and last a long time. They do however have the potential to cause infections in your dog with poor immune systems (although very rare) and have the potential for return to virulence. Return to virulence is chance that the virus will change back to causing the disease you are trying to prevent. This is a theoretic problem, but virtually unheard of. These vaccines can be "contagious." For example if your Maltese is vaccinated with a modified live vaccine for parvovirus it will develop vaccine virus in their stools and shed the vaccine virus for 2-3 days. Although no disease is caused another dog can become "infected" with the vaccine virus and thus vaccinate themselves.

Copyright 1996, 1997© Maltese Only All rights reserved