Parvovirus: odds of a puppy getting it?

September 1, 2009 11:34 PM

I understand the danger parvovirus poses to puppies, but what are the odds of a puppy contracting the disease in the US (specifically Alameda County, California)?

I have been reading about parvovirus in dogs (including this discussion), and understand how serious the illness is.

What I can't seem to find is any indication of risk or prevalance. What are the odds a dog will get parvo, and how many cases of it are there a year in my area?

The more mathematical and bounded the answer, the better. I know I can't be assured to the fifth decimal place about anything, but I want to know: Parvo, this terrible disease, are the odds 1%, 10%, or 100%?

More details below, in the hope that they may allow more exact bounding of the answer.

My dog is five weeks old. He was one of the larger dogs in the litter (with two or three brothers and a sister), which I understand tends to confer longer maternal immunity. I intend to start him on a full vaccine series for parvo.

He's 3/4 Australian Cattle Dog, 1/4 Fox Terrier. He was born in a remote rural area of Humboldt County, California, and as of a few days ago now lives in a semi-urban area in Alameda County.

I keep him mostly indoors, with trips to the back and front yard for exercise. I understand that completely preventing exposure to parvo is impossible (as the virus hardy and survives for long periods in the soil), but also that minimizing exposure to parvo greatly reduces the chances for infection.

I would like to know:

How common is parvo in Humbolt County and in Alameda County? Or, if these specific numbers aren't available, then whatever numbers are available for California or the US. A link to numbers of cases per year would be ideal.

What are the odds of a puppy getting parvo between the ages of 5 and 16 weeks if he's allowed to socialize with a: known dogs (with shots), or b: occasionally visit parks and meet other non-wild dogs.

Links to scholarly papers are fine, and links to the dog equivalent to the CDC would also appreciated.

If this is too specific, or if there isn't enough information, please let me know. Also, I do know how bad the illness itself is.

posted by zippy to pets & animals (10 answers total)

There is an outbreak in SF, and CA is known as one of the three states in which PV is most prevalent (along with FLA and TX). That said, practice common sense, do not allow your dog to walk in areas other dogs may have defecated/urinated (PV can live in soil for long periods of time).

I would be taking him into a specific area for bathroom breaks, and not "exercising" him outside at all. Taking him out while being carried is fine, but I would not be allowing him to walk on the ground in your front yard. Parvo is expensive to treat and often fatal.

As an aside, your puppy is WAY too young to be away from his littermates, is there any chance you can return him to his litter for at least 2 weeks? There are serious problems associated with being taken away too soon, the most critical of which is poor bite inhibition.
posted by biscotti at 5:15 AM on September 2, 2009 [3 favorites]

IANAVet

Specific prevalence numbers on parvovirus are difficult to obtain. However, to get a better idea of the risks in your area, you might contact a local shelter and ask them how many cases of parvo they have run across in the past few months, have they seen an increase, etc. Your vet is also a good source of this kind of information.

Factors that would increase your puppy's risk of being infected are whether or not he went through the shelter system, or has spent time in areas where wild dogs/wolves/coyotes.

I have not read anything about the size of the puppy relative to the length of passive immunity, and am doubtful that would have any major impact. Though I could be wrong and would enjoy reading any research about that issue.

Here is some additional information that may be helpful to you (or others).

Here is the relevant article in the Merck Veterinary Guide for parvovirus. This will give you some more information on the disease itself, symptoms, treatment etc.

The American Animal Hospital Association develops vaccine recommendations for dogs and cats. Here is a link (pdf) to their most recent Canine Vaccination Guidelines. The references at the end have several articles related to parvovirus, mainly on the vaccines and serology. (Note: AAHA designates parvo vaccination as a core recommendation)

If you are deciding whether or not to vaccine your puppy against this horrible disease, you should really include your vet in the decision. They might have more information to help you make a fact-based decision.
posted by gagoumot at 8:56 AM on September 2, 2009 [1 favorite]

I think most vets would tell you that the consequences of Parvo outweigh the expense and trouble of getting the vaccination, regardless of your dog's actual risk. (That's what most vets told me, at least.)
A couple of things you may want to consider, beyond your dog's Parvo risk:
What biscotti said about taking your dog to specific locations for bathroom breaks. Not only will this decrease the odds that he'll get the virus, it will be helpful with house-breaking.

Also, your dog was separated about three weeks too early from his litter, which is kind of significant. Since you are keeping your dog from other dogs (as you should) until he is vaccinated, socialization with other dogs will be extra important in the near future. As soon as your vet says it is safe, you should expose your dog to as many people and dogs as possible. Not doing this can lead to behavioral problems, and since your dog is part fox terrier, you may have more socialization work to do than most dog owners. (Don't mean to disparage the breed- I think they are great.)
posted by Hdog at 9:57 AM on September 2, 2009 [1 favorite]

Nthing the socialization issues. The dogs I have known, that were taken from their litters that early tend to get along fine with people but get into constant serious fights with other dogs. The fights happen so quick, with none of the preliminary growling/raised hackles, etc., that you can hardly react to it. It's a big potential liability, especially if, say, a little kid is walking around with their own dog...
posted by txvtchick at 10:22 AM on September 2, 2009 [1 favorite]

I wanted to clarify a few points in the original post. I am absolutely going to get the puppy vaccinated for Parvo.

Also, by 'exercise' above I meant 'explore the back yard around potty time and tire himself out at his own pace.'

I'm asking about the odds of contracting parvo, so I can understand the overall risk of outdoor activity prior to 16 weeks against the benefits. It's like airplane travel - if it goes wrong, we die a horrible death. But the odds of something going wrong are so low that we accept the danger.

With parvo, I understand the horrible part, now I want to understand the odds.

I don't want to go into socialization or parenting her; there's plenty of coverage on that already (the Ask Metafilter thread I linked to in the intial question is one good discussion). I just want to say that I understand how important socialization and exploration are to puppies, and the reason I'm asking about parvo is because the dog cannot rejoin the litter that he left early, so I want maximize the low-risk chances for him to socialize and explore so that he grows up healthy in body and mind.
posted by zippy at 11:00 AM on September 2, 2009 [1 favorite]

Talk to your vet. When I recently took my puppy in for vaccinations, our vet said that this was an especially bad year for parvo. She not only recommended keeping the puppy indoors, but our other (vaccinated) dog as well out of fear that he might bring it back. After the first two rounds (of three), she told me it was probably ok to bring the pup around dogs that we knew to be healthy and vaccinated, but we stayed out of parks and pet stores under she had finished the entire course of vaccinations.
posted by curie at 3:05 PM on September 2, 2009

We raise purebred dogs and live in fear of parvo. We don't allow non-household members to touch or hold puppies until they are several weeks old. We also don't put them on the ground outside until 7-8 weeks old. When we have little puppies we take extra care with our own shoes not to track into the house if we've been around other dogs. We even go so far as not to set a puppy down on the exam table at the vets if we should have to take a puppy there. In other words, we work very hard to avoid parvo. Parvo is bad, nasty, heartbreaking stuff.

Then again, these are purebred dogs probably with less immune system defenses than a mixed breed dog. Also we live in another part of the country so YMMV.
posted by tamitang at 11:54 PM on September 2, 2009

biscotti, the link you gave on the SF outbreak info led to some good statistics.

In the article, the SF/SPCA says that they normally see 1 case of parvo a month, but that during the outbreak in Nov 2008 they saw 7 cases per month.

The SF/SPCA has total canine intake numbers on their statistics page (see the link for their 2008 stats, PDF).

In 2008 they took in 1353 dogs, or 113 dogs/mo.

So, if my math is correct, the SF/SPCA normally sees 0.9% of dogs with parvo, and in outbreak times, they see 6.2%

This includes stray urban dogs and, by definition, a large number of dogs who have been housed together (dog pounds). So these numbers might be higher than the average for the population.
posted by zippy at 1:00 AM on September 3, 2009

Followup from my vet, who says to take the dog out already.

The vet says: parvovirus is almost nonexistant in my area (Berkeley Hills), the vaccination rate is very high, and poor socialization is a much bigger problem. If the dog doesn't meet lots of people now, he's going to be hard to deal with for life.

The vet says "take your dog to friends' houses and even for walks in your neighborhood. Just avoid parks that are especially for dogs for now." He says that out of 2000 dogs his practice sees, they might see one case of parvovirus per year.

Again, this vet's advice is for an area with a very high vaccination rate, almost no strays, and clean sidewalks.
posted by zippy at 12:52 PM on September 15, 2009

I should add, the dog has started on his vaccinations.
posted by zippy at 12:55 PM on September 15, 2009