Nationwide, fewer than half of all puppies and kittens are vaccinated, according to a study by University of Wisconsin-Madison veterinarians, suggesting that dangerous diseases like distemper and parvovirus will continue to flourish.
“A population must reach a certain threshold of immunity — called ‘herd immunity’ — in order to protect the whole group,” said Ronald Schultz, a vaccinologist who heads a department in the UW-Madison School of Veterinary Medicine. “If not enough individuals in a population are protected, disease can always find a new foothold, or even worse, remain active in the population.”