i think it comes down to how you feel about it, if you think she can cope and if she is otherwise well... also really if you have the time to keep her home, then do so...
I usually just use my judgement, and err on the side of caution - i dont want other kids t get sick and also like DS to be home if he is under the weather - so if I CAN keephim home i do err on the side of doing so even if he would not be excluded.