A recent study, published in the American Journal of Veterinary Researchinvestigated the relationship of E. coli bacteria in people and their pets. This study reported a number of interesting findings:

  • When they compared the molecular fingerprints of E. coli from people and pets, they were the same 10% of the time. This means that E. coli is likely often spread between people and pets in households, although there is no way to know in which direction this occurs. It’s also possible, though less likely, that people are pets don’t transmit E. coli to each other, but rather that they get it from the same source.
  • Antibiotic resistance was common, especially in strains from people.
  • They did not detect an association between bonding behaviors (e.g. sharing the bed, allowing licks on the face) and sharing E. coli. There was, however, an association between having antibiotic resistant E. coli and owners that did not wash their hands after petting their dogs or before cooking meals.

Care should be taken with the study’s conclusion that close contacts like licking aren’t a risk for transmitting germs. They only looked at E. coli, which is but one of many organisms that can be passed between animals and people. Licking of the face, particularly around the ears in children, has been associated with a risk of infection from the multitude of bacteria that are present in the dog’s mouth.

Nonetheless, this study has some good information. My key take-home points are:

  • We routinely "share" bacteria with our close contacts, including our pets. I’ve been saying this for a while, and this is another piece of evidence showing how closely we interact (physically, emotionally and microbiologically) with our animal companions.
  • Handwashing is an important and effective infection control tool.
  • We shouldn’t fear our pets in terms of infectious diseases. There are always risks but for the average person with the average pet, these are very low, particularly is good hygiene practices are used.
  • There are either some dedicated pet owners in Kansas or Dr. Stenske is a very good negotiator.  Getting people to provide stool samples for research studies is usually very difficult! (They’ll give us all the dog poop we want, but getting their own is a completely different story!)

In a University press release, Dr. Stenske sums it up nicely: "We have a lot to learn," Stenske said. "In the meantime, we should continue to own and love our pets because they provide a source of companionship. We also need to make sure we are washing our hands often."