Q. What are the signs of infection? As a child, I was kept away from victims, but I have seen the repulsive lumps on those struck down in later outbreaks, most recently just nine years ago. Giovanni Boccaccio of Florence described the symptoms accurately: "It began with certain swellings in the groin or the armpit. These tumors grew to the size of an egg and soon spread all over the body. After this, black or purple spots appeared on the arms or thighs or elsewhere on the body, sometimes a few large ones, sometimes many little ones." French physician Gui de Chauliac noted that this form of the disease usually causes death in five days, but some people recover, as he himself had. A more deadly form, "with continuous fever and spitting of blood," kills in three days. Other writings suggest a mysterious third form that strikes without symptoms, so sudden that some who retire at night in health are found cold in the morning.