How crowds affect your health

GLASTONBURY 1997, the 2002 Winter Olympics in Salt Lake City, the pilgrimage to Lourdes in 2008: what do they have in common? All three were the backdrop to outbreaks of communicable disease, and so of interest to doctors working in mass gathering medicine. The goal of this relatively young field is to address the specific health problems associated with mass events, but two British psychologists now claim that this can only be done effectively by understanding the psychological transformation that people undergo when they join a crowd…