Is it true? It’s half-true.
Yes, there’s a fairly recent strain of canine parvovirus, CPV-2c, which emerged around 14 years ago, compared to the emergence in the 1970s of the original strain.
No, it’s not deadlier than than “regular” parvo, which can kill puppies and unvaccinated dogs.
And no, the “new” parvo doesn’t somehow evade natural or vaccine immunity. If your dog is immune to one strain of CPV, he’s immune to all current strains.
The parvo vaccine protects against this disease very well in almost all adult dogs, but it’s tricky for puppies. There are also a very, very few adults dogs, known as “non-responders,” who can’t form immunity to parvo from natural infection or vaccines. We don’t really know why, but it’s extremely rare.
So if you have concerns about a parvo outbreak in your area, talk to your veterinarian, especially if you have a dog under 1 year of age, but don’t worry about the “new strain” specifically.
Learn more about CPV, including how to prevent and treat it, here!