2020年经济学人免疫学—初绿萌芽(1)（打印版）

The best hope for ending the covid-19 pandemic is a vaccine. There is no shortage of candidates.

结束新冠疫情最大的希望就是疫苗。有不少候选疫苗。

The World Health Organisation is tracking 34 in various stages of development.

WHO正在追踪34种处于不同研发阶段的疫苗。

How well they will work, though, is another matter.

不过，它们的效果如何则是另一回事。

On September 9th AstraZeneca, a drug firm, announced it was pausing its trials after a participant fell ill.

9月9日，制药公司阿斯利康宣布，由于一名参与者患病，他们将暂停试验。

Such pauses are common in vaccine development, a discipline in which effort does not always bring reward.

在疫苗研发阶段，这种暂停很普遍，在这一学科中，努力不一定总能得到回报。

Despite much research, only an imperfect vaccine is available for dengue fever (it has limited efficacy and can cause nasty side-effects).

尽管进行了大量研究，但目前只有一种不完美的登革热疫苗可用（它的效力有限，并可能引发严重的副作用）。

In 1987 the first trial of an HIV vaccine began in Maryland. Three decades later, the cupboard remains bare.

1987年，第一次HIV疫苗试验在马里兰州开始。三十年过去了，这一领域的成果仍然贫瘠。

The news about covid-19 in two new papers is more encouraging.

两篇新论文中关于新冠的消息更令人鼓舞。

The first, written by a team of scientists at decode genetics, an Icelandic company, and published in the New England Journal of Medicine,

第一篇文章由冰岛一家基因解码公司的一组科学家撰写，发表在《新英格兰医学期刊》上，

reports antibody levels in 1,200 Icelanders who had been infected with the sars-cov-2 virus and recovered.

论文报告了1200名感染新冠病毒并已康复的冰岛人的抗体水平。

More than 90% tested positive for antibodies twice—once immediately post-infection and again four months later.

超过90%的人抗体测试两次均呈阳性——一次是在感染后立即进行的测试，另一次是在四个月后。

People who had suffered more serious disease, such as those who had been hospitalised, developed higher levels of antibodies.

那些状况更严重的人，比如那些已经住院的患者，产生了更高水平的抗体。

So did men and older people, both of whom are at greater risk of more severe illness.

男性和老年人也一样，他们病情严重的风险更大。

The four-month lifespan is cheering for two reasons. Antibodies that hang around are more likely to offer immunity.

四个月的生命期令人振奋的原因有两个。有抗体在就更可能提供免疫力。

That means a vaccine that provokes their production should provide reasonably long-lasting protection.

这意味着一种能够刺激它们产生的疫苗应该可以提供适当的长期保护。

They are also easier to find. That suggests that results from population-wide antibody screening programmes,

它们也更容易找到。这表明，旨在绘制病毒传播图表的

which aim to chart the spread of the virus, should be fairly accurate.

全人口抗体筛查项目的结果应该相当准确。