There are some people with latex allergies who will have an anaphylactic reaction with exposure to latex. In this case, unless the allergic person has direct contact with a balloon, I don't think he/she would be affected with the balloon in the general vicinity. As for airborne exposure to latex, this usually occurs with powdered latex gloves. The latex protein binds to the powder, and when the glove is removed, the powder is dispersed into the air. If this powder is inhaled by someone who is allergic, then a reaction can occur. There is a great web page that describes it all: http://www.cdc.gov/niosh/latexalt.html
Having said all that, I think that banning balloons from a school is as ridiculous as banning peanuts from airplanes and peanut butter in the school cafeterias. If a person has a history of anaphylaxis, they need to use common sense (stay away from latex) and have a dose of epinephrine close by.
If a person has a history of anaphylaxis, they need to use common sense (stay away from latex) and have a dose of epinephrine close by.
Sorry, that sounds suspiciously like "personal responsibility"... We certainly can't have THAT, now can we?