While a Republican legislator calls for additional vaccines for cats, one University of Wisconsin professor’s research shows dogs may be getting more immunizations than they need.

Ronald Schultz, professor and chair of pathobiological sciences at UW, said the new application of information provides evidence that dogs might be being over-immunized for four important diseases, including rabies.

“We were able to use very large research groups, with a broad range of breeds and in large numbers,” Schultz said. “The recommendation is a vaccination every three years for dogs and cats coming into the veterinary medical school at the university.”

In order to determine whether additional vaccinations are needed, medical experts look at the vaccination’s minimum duration, or the least amount of time the immunization will be effective.

“For example, you got immunized for what’s known as MMR, measles, mumps and rubella, when you were in about the first grade and never got it again,” Schultz said.

Schultz said that he had been vaccinated for smallpox as a child and that as part of a class, Schultz tested himself again 50 years after first being immunized. Schultz found he had just as high of a resistance to smallpox as when he was first vaccinated.

“Immunological memory lasts a long time,” Schultz said. “Immunological memory is literally the ability of the immune system to recover from an illness based on what it has seen before. When people who have received the MMR vaccination are exposed to measles, their immune system remembers how to beat it.”

Schultz said the advantage of having a vaccine in your immunological memory is like having learned class material well.

“When you need to find information, you might go look it up in books,” Schultz said. “It’s the same thing, only the immune system doesn’t have time to look it up in books.”

Because the process of vaccination involves injecting a weakened form of a pathogen into a healthy being, it can cause adverse reactions. Immunization against smallpox stopped around 1972, and one of the biggest concerns of health care workers preparing to join bioterrorism response teams is vaccination-induced illness.

“In some animals, in certain breeds and families of dogs, giving a vaccination for a disease is not always necessary and can have some adverse side effects,” Schultz said.

A dog that had already been vaccinated for a disease could experience illness due to a second, unnecessary vaccination. Side effects could include pain, infected wounds, change in hair color, change in behavior and even death.

Schultz said that in certain kinds of sarcoma, five in every 10,000 dogs died because of unnecessary vaccinations.

“Vaccinations are good in general and vital to preventative medical planning. But when we find dogs that are being vaccinated against the disease have a minimum duration of seven years, we don’t recommend giving that vaccination every year.”

Schultz said he had a 15-year old golden retriever who had the same count of antibodies in its system on the day it died as when it was first immunized as a puppy.

Currently the only dog vaccination that is required annually by state law is for rabies. Even with legal implications, not every dog is immunized because of poor or lazy owners, or because they are stray or vagrant dogs.

“If we can get 100 percent of the dog population immunized, it will make it easy to control a disease, but we can never come anywhere near that number,” Schultz said.

Schultz said dogs might also be receiving too many vaccinations for their lifestyle. A lapdog that spends its entire life in an apartment would have almost no risk of contracting an infectious disease and therefore almost no need for an immunization.

“There has to be a match of vaccination schedule with the risk the animal is under. A lapdog might be getting the same number of vaccinations as a dog who is running around outside all the time with other dogs,” Schultz said.

Addressing another animal issue regarding vaccinations is state Rep. J. A. “Doc” Hines, R-Oxford, who introduced legislation that would require vaccinations against rabies for cats, just as for dogs. The bill is currently in the Assembly Committee on Public Health, which Hines chairs.

Hines says he wrote this bill because cat rabies are a public health concern. Previously, Wisconsin law required all dogs get vaccinated for rabies, but cats were excluded in the law.

“The threat of cats is just as strong as it is with dogs,”

Hines said. “Rabies is always fatal. It’s a very serious disease from human health concern.”

Hines said the existing legislation is an oversight — that cats should not be excluded from the rabies vaccination.

Schultz agrees with Hines that rabies is a significant health concern.

“What this law would do is treat cats and dogs more uniformly. We would like to see every kitten get its first rabies vaccine 16-18 weeks after it is born,” Schultz said. “Rabies is a public-health matter because it’s easily transferable to humans and very deadly.”