Chickenpox can be a mild disease for some, but for those with a weakened immunity system, or under treatment for cancer, etc, it can be deadly. The current advice is that children with chickenpox should NOT be be brought into contact with strangers, due to this, until the spots are properly crusted over and dry. They can also pass on shingles, which again can be very painful and extremely serious for some people. Nothing to do with 'fashion'.
As for school trips in term time? It will take me a while to compose a sensible answer, but will get round to it when I have time. I can assure you very few trips would go ahead if that was the case, as the amount of time taken to organise such trips, and the enormous responsibility taken already means that many teachers are no prepared to organise them, even in term time.
Briefing against women ministers in Westminster



