Ground Floor, Please: Q&A with Chris Kandel on Elevator Buttons and Bacteria

More than 200,000. That’s the number of patients who get infections while receiving health care in Canada, every year. More than 8,000 patients die from those infections.

It’s a big problem in part due to the number of places that viruses and bacteria can live in a hospital: ultrasound transducers, white coats, computer keyboards, stethoscopes, cell phones, adhesive tape, even men’s ties. Now, add another to that list — elevator buttons.

Christopher Kandel is a resident in infectious diseases at the University of Toronto. Earlier this month he published a study with Department of Medicine Professor Donald Redelmeier, which showed elevator buttons in three Toronto hospitals had more bacteria than commonly touched surfaces in washrooms.

Most of the bugs the researchers found were harmless, but the study got a lot of media attention and drew an “Eeew!” from many readers. We spoke with Chris about his research, what it’s like to work with a legendary researcher and how hospital visitors should get from floor to floor.

What did you find in this study?
We analyzed 120 elevator buttons and 96 toilet surfaces over several days. We found that bacterial colonization didn’t vary much with button location, panel position within the elevator or day of the week. Most of the bacteria posed little risk to patients, but elevator buttons had notably more colonization than toilet surfaces — 61 per cent versus 43 per cent.

Should we find these results reassuring?
I think so. They reflect low rates of serious nosocomial infections in the hospitals we looked at, and suggest those institutions have good cleaning services and hand hygiene. But there’s still a potential risk to patients due to the frequent use of these buttons by many staff and visitors who may interact with patients. And in a hospital-wide outbreak of a serious pathogen, elevator buttons could be a significant source of infection.

So what should we do when we get on an elevator?
You could activate the button with an elbow or pen. But probably the best thing to do is use hand sanitizers. More hospitals are placing sanitizers in and near elevators, and with public education on the importance of using them before and after touching buttons, more hospitals could limit any risk of transmission.

Where did you get the idea for this study?
During residency rotations in hospitals, I’d seen how many people use elevators and smart phones. I’d been thinking there must be some risk for infection, then one day I saw someone touch an elevator button with a gloved hand while carrying a specimen bag.  When he touched a button I thought, “This needs a study.”

Dr. Redelmeier has done some unique research. He linked cell phone use to car crashes, and showed that poor weather can affect medical school admissions, to take two examples. What’s it like to work with him?
He is helpful in so many ways. His experience and intelligence are second to none, and he was instrumental in teaching me how to design a study. Maybe the key thing I learned from him was to think through every part of a study in advance and write it all down, and to make sure everyone agrees to the plan — including details I wouldn’t have thought about, like the exact time to drop off specimens in the lab. Doing the experiment should be the easy part, and that was certainly the case with this study.

So Dr. Redelmeier was a good mentor?
Phenomenal. And he really cares about his students. I first worked with him between my second and third years of medical school at U of T. We did a study of post-operative pneumonia in patients on proton pump inhibitors, and he would ask about my hobbies and made sure I took time to enjoy them. It’s a kind of holistic approach.

What’s the next step in your career?
Well, I’ve just started a sub-specialization in infectious diseases, and I’d like to do more epidemiology studies of hospital-acquired infections — especially in indwelling devices like pacemakers and prosthetic joints. The number of these infections grows every year, and we’re seeing more resistant strains of bacteria that are very hard to treat. An ounce of prevention is worth a pound of cure, and it’s important to identify those who are at risk of developing these infections.