It then described diseases associated with each season. For example, in spring many people began having mild fevers which, in some cases, caused hemorrhage. The hemorrhage was rarely fatal. Swelling next to both ears was also common. Coughs and sore throats accompanied the other symptoms. Based on modern knowledge, this disease was mumps, which causes salivary glands under the ears to swell. It is remarkable that this ancient work describes symptoms so vividly that modern doctors can diagnose the cause a thousand years later.