I'm currently on cold number 6 since October and utterly fed up with being constantly ill.I work in a school teaching 2/3 mornings a week across the school. I also private tutor, 25 kids a week. So... that's a lot of different children and germs! Most of my tutoring parents are pretty good about requesting online sessions if their children are really coldy (I ask them to do this) but some just ignore me and send them regardless then pretend theyve misunderstood/forgotten. I can't really avoid germy children at school either other than opening windows where possible.What can I do to help build up my immune system? I feel like I'm just lurching from one cold to the next and I'm exhausted.