My wife and I were in Cancun (Riviera Maya) last week, and had a great time...except for the iguana incident.
We were sitting in lounge chairs when an iguana (who I have named Don) walked by. I took this pic of him.
About 30 seconds later he scurried under my lounge chair and hopped up on my wife's lounge chair. Perhaps startled to find someone there, he immediately bit my wife's foot a couple of times, I swept it off the chair, and it sauntered off into the the brush. This was the result of the bite.
We got it taken care of, but then also went to the onsite doctor, who cleaned and bandaged the wound again and gave us topical and oral antibiotics. We'll never be quite so relaxed around iguanas again, who we have always just considered part of the background there. I assume that they have been getting fed, or finding leftover food on chairs, and have learned to be a little aggressive in searching for it.