科学美国人60秒 SSS 天花疫苗可能对预防新冠肺炎有借鉴意义（在线收听）

This is Scientific American's 60-second Science, I'm Susanne Bard.

这里是科学美国人——60秒科学系列，我是苏珊娜·巴德。

Smallpox was eradicated worldwide in 1980. So generations of people have never had to experience the devastation the disease once brought.

1980年，天花在世界范围内被根除，因此几代人从未经历过天花曾带来的毁灭性影响。

"It could cause, sometimes, even in excess of 30 percent mortality. It caused these very painful blisters that covered the entire body."

“天花有时甚至会导致超过30%的死亡率。它会让人全身长满非常痛苦的水泡。”

McMaster University's Ana Duggan. She studies how genomes evolve.

麦克马斯特大学的安娜·达根说到。她研究基因组的进化方式。

The first vaccine for smallpox was developed in 1796.

第一种天花疫苗于1796年研制出来。

It worked by infecting people with pus from pox lesions caused by similar but far less pernicious conditions, like cowpox.

其工作原理是让人们感染痘疹伤口流出的脓来产生免疫，这些痘疹由类似但危害性小得多的疾病（如牛痘）引起。

At the time, no one knew that viruses caused these diseases.

当时，没有人知道是病毒导致了这些疾病。

"We didn't have microscopes that were strong enough to see them.

“当时我们没有强大到足以看到病毒的显微镜。

So we had physicians that were performing this procedure that they knew was beneficial.

因此，我们的医生实施了他们知道有益处的这一程序。

But they didn't understand why it worked. They just knew that it worked."

但他们不明白为何会有效。他们只知道这个方法有用。”

Smallpox vaccination became common in the 19th century. During the American Civil War, all new soldiers on both sides were required to be vaccinated.

天花疫苗在19世纪开始普及。在美国南北战争期间，双方所有新兵都被要求接种疫苗。

"You had a large number of individuals who were congregated in a single place, such as an army barracks, where a disease can spread very easily."

“大量个体聚集在军营等病毒能非常容易传播的地方。”

Back then, there were no mass-produced vaccines.

那时，还没有大规模生产疫苗。

Instead physicians often used fluids and pox scabs collected from previously vaccinated people and shared these materials with each other.

医生们经常从以前接种过疫苗的人身上收集液体和痘疹结痂，之后互相分享这些材料。

They were kept in custom-made vaccination kits—a leather case containing a tin box, glass slides and a lancet for scratching the skin to introduce the vaccine into the body.

它们被保存在定制的疫苗箱里，这是一个皮箱，装有一个锡盒、载玻片和一把用于刮开皮肤让疫苗进入体内的小刀。

Some of these kits were later donated to the Mütter Museum of the College of Physicians of Philadelphia.

其中一些工具箱后来被捐赠给了费城医学院博马特物馆。

Ana Duggan's team recovered fragments of DNA from the kits, piecing together the viral genomes that were in those old vaccines.

安娜·达根的团队复原了工具箱上的DNA碎片，并将旧疫苗中的病毒基因组拼凑在一起。

"We were interested in understanding what virus was being used to protect against smallpox."

“我们有兴趣了解什么病毒被用来预防天花。”

The researchers discovered that the vaccines were all closely related strains of vaccinia, part of what's called the orthopox group of viruses—

研究人员发现，这些疫苗是彼此密切相关的牛痘病毒，属于所谓的正痘病毒属病毒组，

which also includes both cowpox and smallpox.

该病毒组也包括牛痘和天花。

But the vaccinia virus is only distantly related to the variola virus that causes smallpox.

但是牛痘病毒与引起天花的天花病毒关系疏远。

"However, it's still a really effective vaccine.

“然而，它仍然真正有效的疫苗。

So we just had to have a virus that's close enough that induces that immune response that is then protective against future infection.

因此我们只需要有一种与之足够接近的病毒来诱发免疫反应，之后对未来的感染起到保护作用即可。

Vaccinia virus becomes the predominant strain of virus that's used for smallpox vaccination in the 20th century."

牛痘病毒成为20世纪用于天花疫苗的主要病毒株。”

The study is in the journal Genome Biology.

这项研究发表在《基因组生物学》期刊上。

As scientists scramble to develop vaccines for COVID-19, there are parallels to smallpox.

科学家竞相研发新冠肺炎疫苗时，也出现了类似对抗天花的现象。

For example, they're looking into whether less virulent relatives of coronavirus could protect against COVID-19 the way vaccinia protects against smallpox.

例如，他们在研究毒性较低的冠状病毒亲属能否像牛痘预防天花那样预防新冠肺炎。

"We've recently celebrated the 40th anniversary of the eradication of smallpox. And we are now in another global battle for eradication."

“我们最近庆祝了根除天花40周年。我们现在正处于另一场全球消灭战役中。”

Thanks for listening for Scientific American's 60-second Science. I'm Susanne Bard.

谢谢大家收听科学美国人——60秒科学。我是苏珊娜·巴德。