As many people have now heard, a new strain of Parvovirus has been found in Australia. This has produced a large amount of stress and anxiety amongst dog owners.
So what does this new strain really mean to you if you own a dog?
The story in the media:
The media has portrayed this virus as being dangerous to vaccinated dogs and not easily tested for. Media reports talk about two vaccinated dogs contracting the disease, and one out of three affected dogs tested producing a negative test. This all sounds pretty grim.
This virus has actually been around since 2000. That’s 17 years. In this time, it has become the prevalent strain in parts of Europe and South America, replacing the “older” strains. The fact that it has eventually arrived in Australia is not a surprise, and shows just how contagious this virus can be.
Multiple studies have tested the current vaccines available in Australia against this strain, and they have been shown to be effective. The vaccines are just as effective against this strain as older strains.
So why did two vaccinated dogs become infected with Parvovirus?
The clues to that question are in the dogs’ ages. The two affected dogs were less than 12 months old, so hadn’t received any adult booster vaccines. They had received puppy vaccinations, but the final vaccine was given at around 10 weeks of age in both cases.
It has been shown that a small percentage of dogs won’t respond to a vaccine at 10 weeks of age because they still have unusually high levels of maternal antibodies (the antibodies given to them by their mother). These antibodies “attack” the vaccine before the puppy can mount an immune response, which stops the puppy producing its own antibodies. This is why we recommend a final vaccine at 14-16 weeks of age – it captures those small numbers which don’t respond sufficiently to the 10-12 week vaccine.
Why did a dog not test positive to the virus when it was infected?
When we test for Parvovirus, we get a small faecal sample and test for virus particles. The limitation to the test is that infected dogs don’t continuously shed the virus. That means that at the time of testing, the dog may not be passing the virus in the faeces, so the test is negative. Even with the older strains of parvovirus, we only expected 80% of affected dogs to test positive. This means we already understand that the test has some limitations and we respond accordingly. This is nothing new.
So what does this all mean?
The most important thing to understand is that if your dog is fully vaccinated, they are safe. This is not some mutant virus which is going to destroy the dogs of Australia. The vaccines currently used in Australia will protect your dog against this new strain.
The clinical disease caused by this new strain is no better or worse than older strains. They will all make your pet very sick and can kill, so vaccination is still critical.
If your dog is not up to date with vaccinations, or has never been vaccinated, now is the time to act. There is no direct treatment for Parvovirus, so vaccination is the only tool we have. Vaccines are very safe and effective.
If your dog received its last vaccination at 10-12 weeks of age, have a chat to your vet. They may recommend another vaccination to ensure your pet is protected.
If your dog is fully up to date with its vaccinations, there is no need to do anything. Additional vaccinations are unnecessary as your dog will be protected.
If you have any questions or concerns, please contact your vet for further information.