VOA慢速英语:盖茨基金会承诺投入1亿美元对抗新型冠状病毒

epidemic – n. a growing number of cases of an infectious disease in a community

pandemic – n. a situation in which a disease spreads very quickly and affects a large number of people over a wide area or throughout the world

epidemiology – n. the study of how disease spreads and can be controlled