This is disturbing, because death from food poisoning is fairly rare. Usually, food poisoning sets in within five hours of eating the tainted food and most often results in vomiting and diarrhea; the symptoms only become physically dangerous to an otherwise healthy person if dehydration results from massive fluid loss, or from rupturing the esophagus during the act of vomiting.
So....
1. Where was the guy staying, and more importantly, where did he eat his last meal?
2. Is there any mention of the specific bacteria or toxin that killed him?
During my one and only, twelve day trip to Costa Rica, I didn't get sick once. From my first meal at Luka's in El Pueblo through my last C.R. meal (breakfast at my hotel, the Don Carlos), I enjoyed great food from very clean kitchens. Normal precautions, the same ones I'd take in the States were used of course; hand-washing before meal, checking silverware and dishes for obvious contaminants etc. but otherwise I felt completely safe, from the lowest-down small-town soda to the patio restaurant at the Hotel Grano d'Oro.
Wonder what happened and where? Provide more details if you have them, please.
