An epidemic: a disease that spreads rapidly and widely within a particular region or period, infecting many people.
新型ウイルスによる流行病が発生し、国全体で対策が始まった。
An epidemic caused by a new virus occurred, and measures began across the country.
歴史的にはペストの流行病が多くの都市を苦しめた。
Historically, plague epidemics afflicted many cities.
手洗いや予防接種は流行病を防ぐ基本的な方法だ。
Handwashing and vaccination are basic ways to prevent epidemics.