When the last war with Iraq started, the US military began to be vaccinated for Anthrax. Had this vaccine been tried in humans prior to this and are there any known side effects?
Yes it had been tested, mostly in military volunteers. There is a pretty acrimonious literature about it, but I was unable to find a single study that showed convincingly that it is harmful. Nevertheless, 60% of people in the military think it is or may be, and do not want it. This issue was more intense when we believed that there was a risk of anthrax bioweapons in Iraq.
