Here is a possible scenario for the incident in which an innocculation event was closed down out of an abundance of caution : A tiny bit of mass hysteria induced by media and internet claims of harm from the vaccine. Some people are negative about getting the vaccine but coerced into doing so by family etc.. The article gives no details about the "presentation" of these side effects. Fear of needles alone causes many of us to be vulnerable to fainting unless distracted and talked through the esperience. If people are reading about problems on their phones at the inocculation event while they are in line or they see someelse having a "reaction", I can see them reacting in a negative way....psychosomatically......hives for instance.