Hi Hollo - my understanding is that they will have "some" protection after just one shot. My doc explained that this could mean that they could still catch it, however as they would have some protection, they would not get it as bad as they would if they had no injections (hope that makes sense)!

My DD has only had the first injection as unfortunately at the time that she was due for the second she caught a cold. This was also at the time that she had just started day care. So we are waiting for her full recovery prior to getting the last shot.

Janie xxx