Pets whose rabies vaccination has expired will likely survive exposure to the deadly virus if they are quickly given a booster, according to Kansas State University researchers. The discovery also means that pet owners potentially could choose short-term quarantine of such animals at home rather than euthanasia. Many states now require unvaccinated pets that are exposed to rabies to be quarantined for six months at an animal control facility, a costly proposition for owners faced with paying thousands of dollars in kennel bills. “This has the potential to save a lot of pets’ lives,” said Michael Moore, DVM, MPH, the project manager at the Kansas State University Veterinary Diagnostic Laboratory. “Our hope is that now animals with an out-of-date vaccination status that are exposed to rabies will be allowed to be handled the same as dogs and cats with up-to-date vaccinations. They will be given a booster and a 45-day observation at home.” The study, published Jan. 15 in the Journal of the American Veterinary Medical Association, was the first to present scientific data on animals with out-of-date rabies vaccinations, Kansas State reported. Most of the 74 dogs and 33 cats that Dr. Moore and his colleagues examined had rabies vaccinations that had lapsed one to two years before. While some were current on their vaccinations, a few were three to four years behind. Studying the animals’ anamnestic antibody responses, the researchers discovered that neutralizing antibodies in the blood rose when a dog or cat with an out-of-date vaccination received a booster vaccination. “Basically once an animal has been vaccinated, they can receive a booster if they are exposed to the rabies virus,” Moore said. “Then their chances for surviving that virus are very, very good.” The findings do not mean that pets can go without an initial rabies vaccination. The booster is effective only in vaccinated animals, Moore said. Among the other study participants were the Veterinary Diagnostic Laboratory’s Rolan Davis, MS; pathology Professor Derek Mosier, DVM, Ph.D., Dipl. ACVP; and assistant statistics professor Christopher Vahl, Ph.D. About 400 to 500 rabies cases are reported in domestic pets each year, according to the American Humane Association.