Health Care and Epidemics 卫生保健和传染病 Everyone disease at some time or another. However, millions of people around the world not . Sometimes they have no money to . Sometimes they have money, but there is . Sometimes the doctor does not know , and sometimes there is no treatment. Some people doctors. When these conditions are present in large population centers, . 每个人都时不时遭受疾病的折磨。然而,全世界有数百万人得不到良好的卫生保健。有时他们没有钱支付医疗费用。有时他们有钱,但没有医生。有时医生不知道如何治疗这种疾病,有时没有治疗方法。有些人害怕医生。如果这些情况发生在在人口密集的地区,就有可能爆发传染病。