Petting zoos can be great events (I’ve said it before and I’ll say it again!). I end up visiting many with my kids every year.  Despite the fact that a few petting-zoo-associated disease outbreaks also occur every year, and despite the fact that I deal with infectious diseases every day, I still don’t get too concerned about the risk to my family.

Why not?

The main reason is that I can control one of the most important disease prevention measures: making sure my family washes their hands after being in the petting zoo (along with some other common sense measures).

Hand hygiene is a critical infection control tool, and poor hand hygiene practices are often part of the problem in outbreaks. Figuring out how to improve hand hygiene is an important research area, albeit one in which few people are working.

A paper by Maureen and I, published recently in Epidemiology and Infection, looked at hand hygiene compliance in a petting zoo and how to improve it. The study involved using webcams to remotely and discretely observe hand hygiene practices in people attending a petting zoo. We’ve previously done observer-based studies, where you have someone standing there watching, but it’s possible that this method falsely elevates results because some people might notice they’re being watched and be more likely to wash their hands. It’s also easier to record a lot of data and evaluate it over time (i.e. by watching it on video), than try to collect everything accurately in real time.

The published study involved a large petting zoo at the University of Guelph’s annual open house. It’s a well designed and operated event, which needs to be considered when evaluating the results, since petting zoos vary greatly in quality.

Overall hand hygiene compliance at this particular event was 58%. That means 58% of people that came into the petting zoo washed their hands or used a hand sanitizer on the way out. (It doesn’t mean they all did it well, but they at least they did something). In some ways, that number’s good, when you compare to our earlier petting zoo observation study, (or even to results of hand hygiene rates of physicians in some hospitals). However, for such a short-term activity where there is easy access to facilities to wash hands or use a hand sanitizer, there’s much room for improvement.

During the petting zoo, a few thing were changed at defined times to see if they would improve hand hygiene rates. Two things resulted in increased hand hygiene compliance; a combination of petting zoo personnel actively offering visitors hand sanitizer near the exit and improving hand hygiene signs, and having personnel walking through the zoo reminding people to wash their hands. This suggests that people need an active reminder to clean or sanitize their hands. Whether they don’t think about it, or can’t be bothered unless someone points it out, is unclear, but having personnel encouraging hand hygiene is something to consider to help improve infection control. It’s practical for short-term events like petting zoos at fairs and similar exhibits, although perhaps not as practical for permanent exhibits.

People who entered pens or touched animals were more likely to wash their hands than people who didn’t. This is presumably because people who had contact with animals were more likely to recognize a risk. However, while people who touch animals are presumably at higher risk, simply being in the area is enough to pick up an infection. In some outbreaks, people who went into the petting zoo but never touched an animal got sick. That’s why there is a need to remind people that everyone must wash their hands after leaving a petting zoo, not just those who actually petted the animals.

A few other concerns were noted. Despite warnings on prominent signs, 10% of people carried food or drink into the petting zoo area. This probably increases disease transmission risks since people may eat or drink before they wash their hands, or directly contaminate their food or drink while in the petting zoo area.

Overall, hand hygiene rates weren’t bad (and were better than I was expecting), but there is still room for improvement. Considering how quick, easy and cheap it is, there’s no reason not to strive for 100% compliance.