1. Buying goods on the installment plan has become epidemic in recent years.
    近几年来，用分期付款的办法购物十分流行。

2. Violence is reaching epidemic levels.
    暴力达到了流行的程度。

1. 流行：(二)流行 流行(epidemic)是指一个地区某病发病率明显超过历年的散发发病率水平称为流行. 流行与散发是相对的,各地应根据不同时期、不同病种等作出判断. 有时在实际工作中作用暴(或爆)发(性)流行一词. 它表示在一个地区某病病例突然大量增多,

2. 流行性：一个传染病,不论它的杀伤力如何,都会经过三个阶段:零散性(sporadic)、流行性(epidemic)和地方性(endemic). 一个零散性的感染是断断续续、零零星星地出现,会在没有扩散以前就消失掉,也可能进一步发展到第二阶段的流行性.

1. （疾病的）流行，传播
    If there is an epidemic of a particular disease somewhere, it affects a very large number of people there and spreads quickly to other areas.

    e.g. A flu epidemic is sweeping through Moscow.
           一场流感正席卷莫斯科。
    e.g. ...a killer epidemic of yellow fever.
           致命的黄热病的流行

2. （坏事的）盛行，泛滥，猖獗
    If an activity that you disapprove of is increasing or spreading rapidly, you can refer to this as an epidemic of that activity.

epidemic什么意思

    e.g. ...an epidemic of serial killings...
           连环杀人现象的猖獗
    e.g. Drug experts say it could spell the end of the crack epidemic.
           禁毒专家说它可能会结束强效可卡因吸食泛滥的局面。

1. a widespread outbreak of an infectious disease
    many people are infected at the same time

1. (especially of medicine) of disease or anything resembling a disease
    attacking or affecting many individuals in a community or a population simultaneously

    e.g. an epidemic outbreak of influenza