We were at a (very very lovely, and this is just awful) wedding Sat... 14 guests (that we know of, so may be more) have all come down with D&V within the last 18 hours or so.
My gut feeling is that it's a virus... but how do you know? The only reason I'm saying that is a) the timing, wouldn't it be quicker for food poisoning? and b) 2 infants have come down with it and they only ate some peas off the buffet. Also 3 others that we know of (including one child) haven't yet come down with it, yet all ate the food.