大家好，我是J2.
武汉肺炎持续延烧，提醒同学在密闭空间、长时间接触人群时戴口罩，并勤
洗手物摸眼耳鼻。
借由时事顺便来认识一下两个托福也很常见的字：epidemic 跟 pandemic
根据韦氏字典定义，epidemic是an outbreak of disease that spreads
quickly and affects many individuals at the same time, 就是流行
病。
流行病不一定是传染病，例如水俣病是由于环境污染造成的地方性流行病。
pandemic字典的定义是：an outbreak of a disease that occurs over a
wide geographic area and affects an exceptionally high proportion
of the population指的是在广大区域或全球都受到影响的大流行，历史上
曾出现过的pandemic包含smallpox（天花）, 1918 influenza pandemic
(Spanish flu), Black Death(黑死病)。
至于这次的肺炎到底是epidemic还是pandemic呢？
New York Times 在2/2有一篇文章有写到
原文请看https://reurl.cc/lLGL8l
"The Wuhan coronavirus spreading from China is now likely to
become a pandemic that circles the globe.”
还有
“A pandemic — an ongoing epidemic on two or more continents —
may well have global consequences…”
依照现在已至少23个国家都有确诊的情况，可以算是pandemic了。
epidemic这个字托福也出现过喔！例如在讲到Quaternary extinctions in
the New World的理论就提到过。先讲一下背景，Quaternary extinctions
就是第四纪灭绝事件，或称Post-Pleistocene extinctions(更新世末期灭
绝事件)，其实就是大量巨型动物群(megafauna)的灭绝事件, 还是不知道是
哪个灭绝事件吗？就是长毛象、剑齿虎等在冰原历险记卡通里会看到的那些
动物的灭绝事件。
关于这次灭绝事件常见的三大理论有：人类过度打猎、气候变迁，第三个就
是epidemics！
Some have suggested that New World animals might have been
decimated by diseases introduced from Asia during one of the later
intervals when the Bering land-bridge route that connected Asia
with America was open. （有点巧，也是从亚洲开始的...）Such
epidemics, however, usually do not cause species to become
extinct.
但是此理论不太合理的原因是 they decimate local populations over a
large area but generally leave small pockets of resistant
individuals who eventually reestablish the species. 还是有些有抵
抗力的可以存活。
*Bonus
文章最后送给同学实用武汉肺炎关键字列表
传染性极强
the Wuhan coronavirus is highly transmissible
the pathogen is readily transmitted between humans
传染病学模型估计病例应该有十万或更多
various epidemiological models estimate that the real number of
cases is 100,000 or even more
潜伏期
the incubation period is estimated to be between 2 and 14 days
爆发
The 2003 outbreak of SARS