Unfortunately his immune system took a little time getting used to it too. On Friday of the first week in day care, we had an appointment in Anchorage to get his giant head looked at. (Don't worry, it's fine, they just wanted to make sure it was growing normally) By the time we got there, though, he was struggling for breathe and virtually unresponsive! The doctor at the clinic plopped us in an ambulance and we ended up staying at the hospital for a couple of days. Very very scary to watch your child turning blue and fighting to breathe.
He was allowed to go home on Sunday, but he had to have nebulizer treatments for a few more days, and stay home from day care for the next week. Then the next week he ended up with a case of pinkeye! He recovered quickly though, and hasn't been sick much since then.