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艾滋病的崛起

How a Sick Chimp Led to a Global Pandemic: The Rise of HIV

这里是SciShow 我们专讲一些奇妙复杂
Here at SciShow, we talk a lot about the fascinating,
常常还很诡异的探索故事
complicated, and often very weird stories
这些故事导向今天我们所知的科学
of discovery and collaboration that led to the science we know today.
但其中有一个故事
But one of the strangest is something we haven’t covered
我们目前还没完全了解它的所有细节
in much detail before, and it’s a
它也是一个热门话题:几十年来我们一直想弄清楚HIV和艾滋病到底是什么
biggie: the decades it took to figure out exactly what HIV and AIDS were,
以及如何预防和治疗
and how to prevent and treat them.
自从艾滋病危机发生以来
Since the start of the AIDS crisis,
已经有7000万人感染了艾滋病毒
some 70 million people have been infected with HIV,
其中有3500万人死亡
and 35 million of those people have died.
这两个数字都令人惊讶
Both those numbers are staggering in their own way,
放在一起 它们告诉我们
and together, they tell the story
这个疾病已经造成了惊人的损失
of a disease that has led to an incredible amount of loss,
而且还有一点是-如果你
but also one that — if you ’ re
足够幸运得到了对症的药
lucky enough to have access to the right
死亡便不是唯一的结局
medicines — is no longer a death sentence.
因此 在12月1日世界艾滋病日
So, in honor of World AIDS Day on December 1,
我们想告诉你这个故事
we want to tell you that story.
因为有很多内容要讲
There ’ s a lot to cover,
所以我们分成两个部分
so we ’ ll do it in two parts.
在这一集我们来回顾人类是如何发现HIV的
This episode, we ’ ll go over how we figured out what HIV is,
HIV感染什么时候变成艾滋病
when the infection morphs
以及我们认为的病毒的来源
into AIDS, and where we think the virus camefrom.
下一集 我们将回顾最早的治疗方案
Next time, we ’ ll look back to the earliest treatments,
以及抗病毒药物的到来
the arrival of antiretroviral
它将彻底扭转全局
drugs, which were complete game-changers,
然后看看目前科学家们
and go over the creative ways scientists are
正在思考的预防和甚至完全治愈艾滋病的创造性思维
now thinking about prevention and possiblyeven a cure.
首先 最基本的是
But first, the basics.
HIV又称人类免疫缺陷病毒
HIV, or human immunodeficiency virus,
是一种感染人体免疫细胞的逆转录病毒
is a retrovirus that infects immune cells, most
最有名的免疫细胞被称为CD4的T细胞
notably what are known as CD4 T cells.
“逆转录”是指
The “ retrovirus ” part just means
病毒使用RNA:DNA的狡猾
that the virus uses RNA — DNA ’ s more wily,
善变的表兄弟作为基因物质
less stable cousin — as its genetic material,
一旦HIV病毒感染了细胞
and that once HIV infects a cell, it makes
病毒会用一种特殊的酶把自己的基因做成一个DNA版本
a DNA version of its genome with a special enzyme,
然后插入到宿主的基因里
then inserts that DNA into the host genome.
虽然听起来很卑鄙 然而的确如此
If that sounds sneaky — well, it is.
这也是为什么艾滋病毒
And it ’ s part of why HIV
难以治愈的原因之一
has been so difficult to treat, which
下次我们会更详细的讲这些
we’ll talk about more next time.
现在这些被HIV病毒感染
Now, those CD4 T cells that HIV
并且最终被杀死的CD4 T细胞
infects and ultimately kills are a kind of white blood
是一种叫做辅助性T细胞的白细胞
cell known as ‘helper’ T cells.
当意识到有威胁时
When they recognize a threat,
它们会释放出蛋白来引发一系列的
they pump out proteins that help coordinate a bunch of different
免疫反应
immune responses.
你绝对需要它们
You definitely want them around.
艾滋病毒由体液传播 包括血液
HIV is spread by bodily fluids, including blood,
精液 阴道分泌物 母乳
semen, vaginal fluid, and breast milk.
所以艾滋病毒能通过性行为
That ’ s why HIV can be transmitted through sex,
不洁针头 母乳哺育
dirty needles, breastfeeding, and any
以及其他可能交换体液的行为传播
other swapping of fluids you might do
但唾液不属于这种液体
with a major exception: saliva isn’t one of those fluids.
唾液包含了其他物质
Saliva is full of other stuff
能防止艾滋病的传播
that prevents HIV from being infectious,
比如抗体和一些抗微生物的蛋白质
like antibodies and a bunch of antimicrobial proteins.
除非由于某种原因你的唾液中含有很多血液
So unless there ’ s a lot of blood in your saliva
一般来说唾液是无法传播艾滋病毒的
for some reason, it can’t transmit HIV.
一旦某人第一次被感染
When someone is first infected,
他们可能会感觉得了流感
they might feel like they have a bout of the flu, with
伴有发烧 头痛 皮疹 咽喉痛 肌肉以及关节疼痛
a fever, headache, rash, sore throat, andmuscle and joint pain.
那是因为病毒正在大量感染细胞
That ’ s because the virus is infecting lots
免疫系统正在与之斗争
of cells and the immune system is trying to fight it off.
然而在几周之内这些症状就会消失
But within a few weeks those symptoms pass
因为此时这个人已经有了特殊抗体
because by then the person has specific antibodies
能阻止病毒彻底蔓延
that can keep the virus from running totallyrampant.
随后很长时间内他们通常感觉还好
After that, they usually feel fine for a long time —
许多案例显示 这确实是很长一段时间
in many cases, a really long time,
比如几十年
like several decades.
直到某天 他们不这么觉得了
Until, one day, they don ’ t,
因为病毒最终杀死了太多的T细胞
because the virus has finally killed off too many T cells,
导致机体不能正常的抵御病原体
leaving the body unable to properly defend itself against pathogens
即任何可能有危险的或可造成感染的东西
anything that might be dangerous or infectious.
这时候这个人就被称为得了艾滋病
That’s when someone is said to have AIDS,
或获得性免疫缺陷综合征
or acquired immune deficiency syndrome.
通常艾滋病的确诊标准是
Usually AIDS is diagnosed once the person ’
病人的T细胞数量小于每微升血液200个
s T cell count falls below 200 cells per microliter
而正常人的这个值在500-1500之间
of blood, which is well below the normal 500-1500,
或者是出现机会性感染的时候
or if they develop what’s called an opportunistic infection.
机会性感染是指那些
These are infections that anyone
免疫系统健全的人能够抵御并轻易打败的感染
with a reasonably strong immune system would be able to fight off, easy-peasy.
但由于HIV病毒摧毁了大部分T细胞
But because HIV has obliterated most of their T cells,
艾滋病病人就会感染患病
AIDS patients get sick.
甚至死亡
And, they can die.
大多数情况下他们都是因为一次机会性感染而丧命
Most of the time it’s an opportunistic infectionthat killed them.
它们中的一些你可能会比较熟悉
So, some of that was probably familiar to you,
但是试想一下 如果
but pretend for a moment that you ’ ve
你从来没听说过HIV或者我刚才说的其它东西
never heard of HIV or anything else I justmentioned.
因为在80年代时我们并不知道这些基本事实
Because back in the ‘80s, we didn’t knowthese basic facts.
医生们只知道突然之间
All doctors knew was that suddenly,
健康的年轻男同性恋群体中爆发了极度罕见的传染病和癌症
healthy young gay men were developing extremely rare infections and cancers
这些病正在夺走他们的性命
and it was killing them.
UCLA的一名免疫学家是最早注意到这些病人状况的人之一
One of the first people to notice the pattern was an immunologist at UCLA.
在1980年的秋季到来年的春季
Between the fall of 1980 and the following spring,
他看到一连串五个病人
he saw a string of five patients,
都是二三十岁的男性同性恋
all gay men in their 20s or 30s,
他们均患有一种不同寻常的肺炎
with an unusual kind of pneumonia.
他们的肺部生长着一种真菌
There was a fungus growing inside their lungs.
通常情况下真菌无害且绝不会感染肺部
Normally, the fungus was totally harmless and would never infect the lungs,
但这些人却被感染了 而且疾病导致他们呼吸困难
but in these men it had, and it was making it hard for them to breathe.
这些病人也伴有鹅口疮
The patients also had oral thrush
主要是口腔里的酵母菌感染
basically yeast infections in their mouths
而他们的CD4 T细胞几乎消失殆尽
and there are few CD4 T cells.
当这位免疫学家在六月份
By June, when the immunologist wrote up the results
撰写疾病控制中心的死亡率和患病率的周报时
for the CDC ’ s weekly Mortality and Morbidity report
两个病人已经死亡
two patients had died.
一个月后 纽约的一个皮肤科医生
A month later, a dermatologist in New York chimed
也在一份类似的报告中提出了警告
in with a similarly disturbing report,
这次是卡波氏肉瘤
this time with Kaposi ’ s sarcoma,
一种罕见的恶性肿瘤 病人的皮肤上会出现紫色的斑片
a rare cancer where patients develop blotchy purple lesions on their skin.
在两年半内26个纽约和洛杉矶的男同性恋
In two and a half years 26 young gay men in New York and LA
陆续被诊断为卡波氏肉瘤
had been diagnosed with Kaposi ’ s.
有一些人还患有奇怪的真菌性肺炎并有八人死亡
Some also had the weird fungal pneumonia,and 8 had died.
现在你可能很难想象 但在当时
It ’ s hard to imagine now, but at this point,
科学家完全不知道他们生病的原由
scientists had no idea what was making people sick.
也不清楚病因是否是来自于某种毒素或病原体
They didn ’ t know if it was some sort of toxin or a pathogen.
如果它是某种形式的感染
And if it was an infection of some kind,
他们不知道它是如何传播的
they didn ’ t know how it was spreading.
这意味着无法提醒人们如何保护自己
That meant they couldn’t warn people abouthow to protect themselves.
然而它和男同性恋的联系是非常显著的
The association with gay men, though, was certainly striking,
因此在早期很多人称
and early on, many called
这种神秘的疾病为GRID-同性恋相关免疫缺陷
the mystery disease GRID, for gay-relatedimmune deficiency.
更多的人叫它
Lots of people would talk
“同性恋癌症”或“同性恋瘟疫”
about it as the “ gay cancer ” or “ gay plague. ”
但这个疾病并不局限于男同性恋
But the disease wasn’t limited to gay men.
它也高发于
It was turning up
血友病患者 — 那些血液不能正常凝固
in hemophiliacs — people whose blood doesn’t clot properly and are
而需要用其他人血液中的凝血因子治疗的人
treated with clotting factors taken from otherpeople’s blood.
医生们也在静脉吸毒者
Doctors were also seeing cases in IV drug users,
女性 婴儿 和异性恋男人当中看到这样的例子
women, infants, and heterosexual men.
特别是有20个近期从海地移民来的患者
In particular, 20 recent immigrants from Haiti had gotten sick,
他们中没有人说自己是同性恋
and none said they were gay.
这些证据是很重要的
Those clues were important,
因为这告诉科学家这种最终
because they told scientists the disease — which had finally
被命名为艾滋病的疾病可能是感染性的
been given the name AIDS — was probably infectious,
并可能是通过血液传播的
and probably transmitted by blood.
也有其它疾病通过这种方式传播 比如乙肝
There were other diseases that spread in similar ways, like hepatitis B.
因此在1983年3月
So in March of 1983,
CDC警告医生们对于输血要更加谨慎
the CDC issued a warning that doctors needed to be careful about blood
以及这个疾病看起来
transfusions, and that the disease seemed to spread
通过同性恋和异性恋均能传播
through both gay and straight sex.
有关一些细节的争议
Debates about the specifics,
包括其是否通过唾液传播是在后来讨论的
including whether it could spread through saliva, would happen later.
而什么是感染源呢?
But what was the infectious agent?
科学家们开始了寻找致病原因的竞赛
The race was on for scientists to figure out what was causing the disease.
法国分子生物学家Luc Montagnier怀疑是一种病毒
French molecular biologist Luc Montagnier suspected a virus
因为在那个年代
because at the time, the
血友病病人用的血制品会被过滤掉细菌或真菌之类的东西
blood products hemophiliacs used were filtered for things like bacteria and fungi.
但病毒由于太小无法过滤
But viruses were too small to catch.
他同他的同事Françoise Barré-Sinoussi一起
So along with his colleague Françoise Barré-Sinoussi,
研究了艾滋病病人的细胞
he searched cells taken from AIDS patients
发现了一种逆转录病毒
and found a retrovirus.
几乎在同时
Around the same time,
美国NIH的Rebert Gallo也从艾滋病病人的样本里
Robert Gallo at the NIH in the US also identified a retrovirus
识别出了一种逆转录病毒
in samples from AIDS patients.
两组科学家同时在1983年5月发表了他们的研究成果
Both groups published their work in May 1983,
不久之后另一个研究团队
and shortly afterward another team found yet
也发现了另一种逆转录病毒
another retrovirus.
所有这些病毒都被起了不同的名字
All the viruses had been given different names, and at first,
最初的时候
it’s wasn’t totally obvious
还不能明显看出它们是同一种东西
that they were the same thing.
但它们是 到了1986年艾滋病被官方命名为HIV
But they were, and in 1986, the cause of AIDShad been given an official name: HIV.
于是HIV就成了众矢之的
So, HIV was the problem,
但它源自何处 又为什么会在
but where had it come from, and why had the epidemic struck
爆炸头和迈克尔·杰克逊时代大爆发?
now, in the decade of big hair and MichaelJackson?
在一些研究者正在争先恐后的
While some researchers were scrambling to
寻找艾滋病感染病因的时候
identify whatever it was that made AIDS infectious,
其它研究者注意到恒河猴也患有类似艾滋病的疾病
others noticed that macaque monkeys also seemed to suffer from an AIDS-like disease.
一个研究组决定采集一些患病猴子的血样
One group decided to take some blood samples from these sick monkeys
1985年他们发现了与HIV相似的病毒
and in 1985 they found a virus that was similar to HIV.
最后被命名为SIV 即猿猴免疫缺陷性病毒
It was eventually called SIV, for simian immunodeficiencyvirus.
研究者开始思考HIV病毒
Researchers started to think that HIV
可能是从我们的灵长类亲戚跨物种传播过来的
might have come from our primate relatives, jumping the species barrier.
在大量的研究以后
After a lot of work,
他们发现在流行病背后的病毒
they figured out that the virus behind the epidemic was very similar
与黑猩猩患有的猿猴免疫缺陷性病毒非常相似
to the chimpanzee version of SIV,
是它们将病毒传递给了我们
and they were the ones who had passed it to us.
但这究竟是如何传递的呢?
But how exactly?
没有确切的方法能够知晓细节
There ’ s no real way to put this delicately,
但大部分科学家同意
but most scientists agree that the reason
猿猴免疫缺陷病毒跨物种传播到人类身上的原因
why SIV made the leap
也称为溢出到人类的原因是
into humans — what ’ s called a spillover — is because we had a
人类对野味的喜好
taste for bushmeat, or wild game.
在这里 野味指的是猴子和黑猩猩
In this case, monkeys and chimps.
这被称为切割猎人假说
This is known as the cut-hunter hypothesis.
在屠宰黑猩猩的过程中
In the course of butchering a chimpanzee,
一些被猿猴免疫缺陷病毒感染的黑猩猩血进入到
some SIV-infected chimp blood enters a small
猎人手上的小伤口里
cut on the hunter’s hand.
或是一些血喷溅到嘴里
Or, a bit of blood splatters in their mouth.
这让病毒足够接近人体并感染猎人
The virus is close enough to human biology to infect the hunter,
经过一段时间
and over time, if the
猎人把病毒传播到足够多的人
hunter passes the virus along to enough people,
然后进展为今天我们知道的艾滋病
it evolves into the HIV we know today.
像这样的溢出发生过很多次
Spillovers like these happened many times
我们之所以能这样说是因为
— we can tell because the virus mutates
病毒变异非常快 通过基因的差异
quickly, and by looking at genetic differences,
我们可以识别出多个族系的病毒
we can identify multiple lineages of the virus,
每一个都对应一种溢出
each one corresponding to a spillover.
我们已经追踪到目前流行的只是归结于
We ’ ve traced the current epidemic to just one
它们中的一种 叫M系
of these, called ‘ M ’ for main.
通过分析黑猩猩的尿液和粪便
By analyzing chimpanzee pee and poop,
研究者相信把病毒传播给人类的黑猩猩
researchers think the chimps who passed that version of
生活在喀麦隆西南部
the virus to us lived in southwestern Cameroon,
靠近刚果的森林里
in the forests near the Congo.
我们能找到的最古老的
And based on the oldest blood samples we can find
已知其中含有HIV病毒的血样
that we now know have HIV in them, which
来自1950年和1960年
are from 1959 and 1960,
科学家估计HIV-1第一次感染人类在1908年左右
scientists estimate that HIV-1 first infected humans around 1908.
看上去是很久以前了
If that seems like a long time ago, well,
因为病毒花了一段时间才爆发
it takes a while for a virus to take off.
到1920年代
By the 1920s, it ’ s thought
病毒被认为开始通过人类传播到下游
that the virus traveled downriver — in a person, of course
一个蓬勃发展的城市金沙萨
— to the burgeoning city of Kinshasa,
当时是比利时殖民地利奥波德维尔
then known as the Belgian colonial city of Leopoldville.
在那里除了妓女外没有其他更多的女人
There weren ’ t many women around other than prostitutes,
所以专家们认为HIV通过那种方式传播
so experts think HIV spread that way, and possibly
也可能通过殖民者为抵御一些热带疾病和性病
through injectable drugs the colonists used to treat some tropical
而注射的一些药物
and venereal diseases.
那时还没有一次性注射器
This was before disposable syringes,
护士通常需要治疗大量病人
and nurses were trying to treat lots of people with just
但只有几个注射针筒
a few of them,
因此这些注射针筒在给下一名病人使用之前
so the syringes may have only been rinsed with alcohol before being used
仅仅是用酒精浸泡了一下
on the next patient.
所以这种本来想要预防疾病的治疗方式
So the very methods meant to stop the spread
事实上却助长了疾病的肆虐
of disease may have actually been encouraging it.
随着时间的推移在金沙萨感染的人到了其它的地方
With time, infected people in Kinshasa left to go to other places,
他们不可避免的
and they did the unavoidable:
把病毒传播给了别人
they brought the virus with them.
因为病毒的变异非常快
Because the virus mutates so quickly,
我们可以通过把病毒分成9个亚型
we can group the viruses into 9 different subtypes
来感觉一下HIV病毒是如何从中非传播到世界的
and get a sense of how HIV traveled around the world from Central Africa.
几种亚型传播到了非洲的其它地域
Several subtypes spread to other parts ofAfrica.
亚型C向南传播后登陆印度
Subtype C went south and then landed in India.
亚型B去了海地
Subtype B went to Haiti — and then,
然后经过几个历史性的转折来到美国
through several quirks of history, came to the US.
首先在1960年 当比利时人离开刚果
First, in 1960, when the Belgians left the Congo,
讲法语的海地人开始到达刚果
French-speaking Haitians started to arrive in the Congo to
并从事医生、律师和其它一些专业方面的工作
work as doctors, lawyers, and other professionals.
但随着1965年扎伊尔的成立
But with the creation of Zaire in 1965,
外来移民渐渐变得不受欢迎
the immigrants felt unwelcome, so they went back
所以他们返回海地并把HIV也带了回来
to Haiti, bringing HIV with them.
在这里HIV病毒迅速扩散
There, HIV expanded especially quickly,
有可能是因为这里的一个血液中心
possibly because of a plasmapheresis center where people
在这个中心里献血者可以得到钱
could get paid to donate their blood plasma.
而中心使用的装置混合了不同献血者的血液
The center used a machine that mixed the blood
从而导致了病毒的传播
of different donors, allowing viruses to transfer.
1982年在太子港的一个贫民窟里
By 1982, nearly 8 percent of a group
几乎8%的年轻母亲都是HIV感染阳性
of young mothers in a Port-au-Prince slum were HIV-positive
这是一个令人非常震惊的数字
— an astoundingly high number.
HIV被认为是在1969年左右进入美国
HIV is thought to have entered the US around 1969,
仅仅是通过来自海地的一个感染者
with just one infected person or unit
或者一个单位的血浆
of plasma from Haiti.
人们大约花了十年时间才注意到它
It took about a decade for anyone to notice,
但这时候已经太晚了
but by then it was too late.
HIV不仅在美国已经开始流行
The epidemic had begun, and HIV was not only in the Americas,
而且在欧洲和亚洲也是
but Europe and Asia, too.
而现在的问题是
And now that it was here,
我们需要找到战胜它的方法
we needed to figure out how to fight it.
我们会在这个迷你系列的下一期讲述这一点
But we’ll get to that in the next episode of this mini-series.
同时 感谢收看本期的SciShow
In the meantime, thanks for watching this episode of SciShow,
如果你还想学习更多有关HIV的知识
and if you want to learn
以及其它各种各样的科学知识
more about HIV and all kinds of other science,
欢迎访问和订阅youtube.com/scishow
you can go to youtube.com/scishow and subscribe.

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译制信息
视频概述

一只生了病的黑猩猩给人类带来的灾难

听录译者

收集自网络

翻译译者

jameschan

审核员

审核员 D

视频来源

https://www.youtube.com/watch?v=izwomieBwG0

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