Information about Parvo

[mrsgrubby]

I took a class yesterday on Parvo and since there have been quite a few posts about Parvo lately I thought I would share what I learned. I hope it helps answer some questions.

This information comes from Dr. Clark at the Mancelona Clinic in Michigan:

Parvo is caused by a virus in the family parvoviridae. The virus is very resistant to environmental deactivation. Viable Parvo virus can be pulled out of the ground three years after it was deposited. Cold actually helps preserve the virus, so areas with hard winters will preserve the virus longer.

The signs of Parvo are vomiting, diarrhea, (often bloody), listlessness.

Parvo affects the cells of a dog by indecting DNA/RNA into the cell and the cell ends up dying.

Dogs get Parvo through the oral/nasal route. It only takes 100 viral particles to infect a dog, and on average there are 95 million viral particles per gram of infected feces.

The virus goes to the tonsils and stays there 2-5 days. Then it gets into the blood system and begins affecting the rapidly dividing cells, like bone marrow, where is suppresses white blood cells, lowers immunity thus many dogs get secondary infections. It also attacks the intestinal crypt cells and kills them causing the diarrhea and problems with absorbing nutrients.

Untreated Parvo has a 90% fatality rate due to dehydration and secondary infections and loss of crypt cells. However, timely medical intervention increases survival 60%-80%.

Parvo usually affects puppies with 0-1 shot so far in the series. Your vet will check for the disease through the ELISA test of feces, or looking at the white blood cell count.

How does the medical intervention work? First vets work to correct the dehydration and restore the electrolyte balance. Then they give antibiotics for the secondary infections. The antibiotics will not work against the Parvo its self. Sometimes vets administer Hyper Immune Serum taken from a healty dog and injected under the skin of the sick dog. (this is not super common as it can cause other issues). Comforting the dog is also important as it is vomiting and often vets give Metoclopimide which is an anti vomit medicine.

Dogs will normally spend 3-5 days on an IV and once they can hold food and water down they can go home.

Once your dog is home, make sure that you clean up any feces right away and spray area with a bleach/water solution, especially indoors, but outdoors is good too. (The solution will probably kill your grass but since the virus can hang around three years, the dead grass is probably worth killing the virus.)

Parvo is 99% preventable with vaccines. Puppies should not be socialized until the shots are completed. The vaccines allow the body to respond to the disease without actually getting the virus.

Puppies mothers usually provide maternal antibodies to them. They are passed to the puppy through the placenta, and through the colostrum. The protection from the mother usually lasts 12-14 weeks.

Because no one knows for sure how long the maternal antibodies will be effective, multiple shots are required. As long as the antibodies exist, they will bind up the vaccines and not allow it to properly work. The last shot must be given after the puppy is 14 weeks of age.

I hope this helps understand the disease that most puppy owners fear.

[Buddy_DaMutt]

Thanks. You hear a lot about it, but no one ever explaines it. Ya know?

[aspen]

excellent post!

Did Dr. Clark say anything about whether yearly boosters are needed or evey three years as it is now recommended?

[Jamilupine]

Thank you for all the information!

[mrsgrubby]

Aspen.
Dr. Clark said that at this time the vaccine manufacturers are not willing to guarentee that every three years will keep your dog healthy. Once they do, if a dog gets sick, the manuafacturer will pay the vet costs.
He said his gut is that every 3 years would be fine for a dog older than 8 years old. But until the manufacturers agree to guarentee the vaccine, he will suggest every year.