Within a certain range on the lower end, definitely. Above that range, I disagree strongly. People generally know when there's "a bad cold/flu going around" o

Within a certain range on the lower end, definitely. Above that range, I disagree strongly. People generally know when there's "a bad cold/flu going around" or "a stomach bug" or w/e. There's some good intuitive reasoning there, but I'd agree that they aren't very good at it within a regime where it's prevalent enough to matter, but not quite prevalent enough to see/feel out intuitively.