We have a small group - seven people, mid-twenties - who are, for all intents and purposes, cast out into the wilderness on their own. They were reasonably healthy when they got there. They are alone for about six months (maybe - I'm not sure about the time frame yet). Would any of them suffer from things like a cold, the flu, a sinus infection, or a sore throat? Would someone have to actually have the condition to pass it on to someone else, or could it produce itself (or something similiar) without having character A give the sniffles to character B?
Aside from bumps, bruises, scrapes, stomach upset from food, general headaches, and tooth problems, what small ailments could someone in an isolated group suffer from? I don't want anyone dead - that I know of, yet - but I would like to have as many sharp sticks as possible to use for poking at them when I need some action.