這個例子很重要。這個病人傳了最少13人
“In that time he passed it onto at least 13 people, including his wife Valentina, a friend he went jogging with, two doctors, his GP, three elderly pubgoers and a 77-year-old woman who was killed by the disease.” 其中一個朋友一齊去跑步,但馬拉松(比平常跑步人多和長時間)卻未有報告個案。所以高危就是朋友聚會、酒吧、醫護等