LimitIsUp seeing your comment about how other students feel about catching your DD's cold gave me a flashback to the annual awards night at DS2's school in July.
There was a special section - 10 mins of my life in the suffocating heat! - dedicated to students who had 100% attendance records. I think there were about 4 students who hadn't had a day off since they joined the school (and one of them had just done his GCSEs).
I was probably a bit irritable because I was hot, uncomfortable, bored etc but I remember thinking that there is no way they haven't ever had anything infectious during term-time, its just they came in anyway, probably struggled to learn anything that day but spread their bugs to 30 others.
Actually, I was grumpy looking back, because I definitely remember thinking: "OK, i've got the message, now can you just move and speed up a bit before I faint?"