A staph infection that can kill humans is being seen more often in cats and dogs, and veterinary researchers are trying to determine whether that might spell danger for pet owners.
The Ohio State University College of Veterinary Medicine has begun a study to determine the prevalence of methicillin-resistant Staphylococcus aureus, or MRSA, in small animals.
MRSA is a zoonotic pathogen, which means that it can be passed from animal to human and vice versa.
The number of animal cases has not been documented, but more have been showing up, said Dr. Armando Hoet, an OSU clinical assistant professor in veterinary preventative medicine who is working on the study.
"In the last two years, we have seen strains not seen before in animals," Hoet said.
Since 2005, 34 separate studies have been published on MRSA infections in dogs or cats, more than three times the number from 2002 to 2004, according to Medline, a medical database.
Dr. Robert Knapp said he has seen a couple of MRSA infections this year at the Knapp Animal Hospital in Clintonville. MRSA in animals is a growing concern for vets, but still "very uncommon," he said.
The Columbus Health Department has not been notified of any cases of animal MRSA, and the Ohio Health Department has had only one report this year. Neither doctors nor veterinarians are required to report the infection.
It's just as likely someone would catch MRSA from the general environment as from a pet, said Melissa Brewer of the Ohio Department of Agriculture. However, Hoet said that screening the pets of a person infected with MRSA might be an important part of recovery.
A 2004 report by the national Centers for Disease Control and Prevention detailed the case of a Dutch woman who contracted MRSA. She was treated and tested negative, but a follow-up test found a positive result.
Her dog tested positive for MRSA and was treated. After that, the woman did not test positive for MRSA again.
Treating such multiple infections is expensive, Hoet said. Also, when antibiotics don't eliminate the bacteria, more-resistant strains of staph can develop. That's a key concern in the medical community.
Hoet recommends having pets tested for MRSA if they already have a staph infection or if their owners are at risk of developing one. People at risk include those with chronic diseases such as diabetes and AIDS, those who have recently had major surgery and the elderly.
However, he cautions people not to overreact and get rid of their pets.
"You're much more likely to get an infection from your friend than your dog," he said.
One of the main goals of the OSU study is to try to determine how many animals in the general population are carrying MRSA without showing signs of illness, he said.
About 2.5 million Americans carry the germ, according to a study by Columbia University. Not all will show signs of infection. But an estimated19,000 people die from MRSA each year, according to a study published in the Journal of the American Medical Association in October.