I wonder how many of those infections involved children and free range chickens. It's easier to contain chicken germs if the chickens themselves are contained, then the kids wash their hands when done with the chickens and go about their business playing in the yard and licking their toys or whatever. But if the chickens have free reign of the whole yard and poop everywhere, there's practically no safe time and place to play in the yard. Little kids are dumb. They will lick everything (I know, I have two of them). That's why the thought of poopy little chicken feet walking all over everything in the yard grosses me out beyond measure. Perching on the lawn furniture... Stepping on the little shovels and buckets and toys... digging in the sand box... Ew! Do you sanitize everything when you have a cookout then? Cookouts are the perfect context for putting fingers in your mouth even for people that don't normally do so. If your chickens use your lawn furniture, and you have cookouts without sanitizing everything, I can totally see how grown adults can get infected without being in the category of people who lick their chickens...