I definitely follow the rule. The only exception occasionally would be my little guy. He's a puker. He has various medical problems that cause vomiting that are unrelated to an acute illness. But I can tell the difference between a stomach bug & his tummy troubles (EE). If I suspect it's a virus, it's 24 hours vomit, diarrhea & fever free to return to school.
Mom to my girls ('94), ('99) & ('02)
And my little guy (12/09)