Prof discovers MSRA can be passed between humans and their pets
BY LORI BONA HUNT
Since his new study on the drug-resistant “superbug” methicillin-resistant Staphylococcus aureus (MRSA) came out last month, Prof. Scott Weese, Clinical Studies, has been busy answering phone calls and e-mail messages from the press and public.
Published in the journal Veterinary Microbiology, the study found that MRSA can be passed freely between humans and household pets and that animals can act as silent carriers of the bacterium for several months.
For Weese, the research simply confirmed what the infectious disease expert and other veterinarians have long suspected: there is more exchange of infectious agents between humans and animals than previously recognized.
But for other people, it was big news. “I've been doing a lot of TV and radio interviews and answering questions from the general public,” he says. “I've been telling people that this really just reinforces something we've been saying for years — that pets and their owners are not separate entities; they're closely integrated parts of the greater animal population. Although transmission of diseases from animals to humans is a well-understood concept, the role of household pets has not received much attention.”
The research is the latest in a series of studies Weese has done on the transmission of diseases between animals and people. His work has included studying therapy dogs in hospitals, MRSA in horses and even petting zoos. The research includes determining which disease strains humans and animals have in common and which may be unique to a particular species.
“Although MRSA can clearly be transmitted between animals and people, there are other times when animals are blamed, probably unjustifiably, for spreading diseases to humans,” he says.
In earlier research, Weese found that MRSA could be passed from humans to mammals. His new study focused on showing how transmission can take place both ways between people and pets.
MRSA is a version of a common bacterium carried on the skin and in the nose that can cause skin, soft-tissue and other infections. It's resistant to many common antibiotics, which can make treatment more difficult. In most cases, MRSA causes no or very minor symptoms, but in rare cases, it can lead to death, even in otherwise healthy people.
The fact that MRSA can be passed back and forth between animals and humans does raise some concerns about how to best control the pathogen, says Weese.
In the new study, he cites cases where patients who were successfully treated for infections became ill again after contact with a pet.
But he's quick to add that pet owners shouldn't overreact.
“Just like people can catch things from other people, they can possibly catch things from their pets, too. It's not common or likely, but it can happen. There has always been some degree of risk in pet ownership, but the overall risk is low and the beneficial aspects of pet ownership cannot be ignored.”
Weese adds that in the typical household with pets, the humans are the ones in contact with large numbers of other people and animals, not the other way around. “Odds are that the pet was infected by its owner in the first place.”
