The outbreak began in December.
疫情始于去年12月。
The repeated mingling of people and animals in China means that viral mutations that infect humans are likely to arise there; and mass migration to cities means that they are likely to spread between people.
在中国，人和动物的反复混合意味着可能会出现感染人类的病毒突变；大量的人口迁移到城市意味着他们很可能在人群中传播。This virus probably originated in bats and passed through mammals, such as palm civets or ferret badgers, ending up in Wuhan\'s wet market, where wild animals were on sale.
这种病毒可能起源于蝙蝠，通过哺乳动物传播，如棕榈果子狸或雪貂獾，最后出现在武汉的野生动物市场。
Symptoms resemble flu, but can include pneumonia, which may be fatal.
症状类似于流感，但发展成肺炎会致死。About 20% of reported cases are severe, and need hospital care; about 2% of them have been fatal.
约20%的报告病例症状很严重，需要住院治疗；其中约2%是致命的。
As yet, there is no vaccine or antiviral treatment.
到目前为止，还没有研发出疫苗或抗病毒治疗方法。
The greatest uncertainty is how many cases have gone unrecorded.
最大的不确定性是有多少病例没有被记录在案。
Primary health care is rudimentary in China and some of the ill either avoided or were turned away from busy hospitals.
初级卫生保健是最基本的，一些病人的传染本是可以避免的，又或者是无法被负荷过重的医院接收。
Many more may have such mild symptoms that they do not realize they have the disease.
更多的人可能症状非常轻微，以至于他们没有意识到自己得了这种病。
Modeling by academics in Hong Kong suggests that, as of January 25th, tens of thousands of people have already been infected and that the epidemic will peak in a few months\' time.
香港学者建立的模型显示，截至1月25日，已有数万人感染，疫情将在几个月内达到顶峰。
If so, the virus is more widespread than thought, and hence will be harder to contain within China.
如果是这样的话，这种病毒的传播范围比想象的要广，因此在中国将更难控制。
But it will also prove less lethal, because the number of deaths should be measured against a much larger base of infections.
但它也将被证明不那么致命，因为死亡人数应该与更大的感染基数进行比较。
As with flu, a lot of people could die nonetheless.
就像流感一样，也有很多人会死。
In 2017 - 18 a bad flu season saw symptoms in 45m Americans, and 61,000 deaths.
2017年至2018年，严重的流感季节导致4500万美国人出现症状，6.1万人死亡。
Scientists have started work on vaccines and on treatments to make infections less severe.
科学家已经开始研究疫苗和治疗方法，以降低感染的严重程度。
These are six to 12 months away, so the world must fall back on public-health measures.
但至少还需6到12个月的时间，所以世界必须依靠公共卫生措施。
In China that has led to the biggest quarantine in history, as Wuhan and the rest of Hubei province have been sealed off.
在中国，新冠病毒导致了历史上最大规模的隔离，武汉和湖北省其他地区已经被封锁。
The impact of such draconian measures has rippled throughout China.
这些严厉措施的影响已波及整个中国。
The spring holiday has been extended, keeping schools and businesses closed.
春节假期延长，学校停课、企业停工。
The economy is running on the home-delivery of food and goods.
社会运行全靠食物和商品的送货上门。