Well, then I'd take it that many schools banning peanut butter outright due to the fractional number of kids with peanut allergies is... overreaction?
http://fox13now.com/2013/04/26/boy-11-dies-after-severe-alle...
https://www.ncbi.nlm.nih.gov/pubmed/10200001
This includes tree nut allergies as well. The short of it is that 0.6% of children under 18 in this study were found to have peanut or tree nut allergies. If this is true, that means many schools will probably have fewer than 5 students with the allergy.
In this case, outright bans seem to be more about reducing potential liability in the face of activist or litigious parents than they are actually addressing a student health issue.
My understanding of this type of reaction is that it doesn't require a large volume of the allergen to cause a very serious response. Trace amounts can be very dangerous. So it seems impossible to guarantee prevention by banning foods.
In my opinion, kids need to be aware of what they can and cannot eat, and the school must be prepared to actually deal with a reaction situation instead of just saying 'look, we banned peanut butter, what else do you expect?'
Anaphylaxis from food can take a while (up to an hour or two I believe) to set in. When it does, it can cut off an airway, and then you're basically racing against suffocation with an epipen. If the kid's outside at recess or in the bathroom alone or just slow to tell a teacher, you're in a bad situation.
I don't know how much gluten it takes to trigger some of the scarier symptoms of IBD or if any of them are lethal in children. My guess is they're not, just because I haven't heard of gluten bans in schools.
It was... bad. Another classmate also ended up hospitalized with a celiac diagnosis. Whether it was brought on by food, I don't know, but the prevalence of wheat in a standard American diet could lead one to believe so.
It definitely shouldn't.