Romina Libster: The power of herd immunity (with English subtitles) | TED

Translator: Gisela Giardino Reviewer: Romina Pol

譯者: Felcia Lau 審譯者: Bighead Ge

One of the first patients I had to see as a pediatrician was Sol,

成為小兒科醫生後

我要接見的第一個病人叫索爾

a beautiful month-old baby

是一個很美麗的彌月嬰兒

who was admitted with signs of a severe respiratory infection.

她患有很嚴重呼吸道感染的徵兆

Until then, I had never seen a patient worsen so fast.

直到那時為止

我從未見過一個病人惡化得那麼快

In just two days she was connected to a respirator

只在兩天裡，她就要接駁呼吸器

and on the third day she died.

第三天她就離世了

Sol had whooping cough.

索爾患上了百日咳

After discussing the case in the room and after a quite distressing catharsis,

在房間裡經過一番討論

經過很令人心痛的宣泄之後

I remember my chief resident said to me,

我記得我的總住院醫師曾經對我說：

"Okay, take a deep breath. Wash your face.

「好了，深呼吸，洗個臉吧

And now comes the hardest part:

現在才是最困難

我們要向她的父母解釋。」

We have to go talk to her parents."

At that time, a thousand questions came to mind,

那時候，我腦海裡出現很多問題

從「怎麼一個彌月的嬰兒會這麼不幸？」

from, "How could a one-month-old baby be so unfortunate?"

to, "Could we have done something about it?"

到「我們是否能做些甚麼呢？」

在疫苗出現之前

Before vaccines existed,

many infectious diseases killed millions of people per year.

很多傳染病每年奪去數百萬人的性命

During the 1918 flu pandemic

1989年流感大流行時期

50 million people died.

5千萬人死亡

That's greater than Argentina's current population.

比阿限廷現在的人口還多

或許，在座有年紀大一點的會記得1956年在阿限廷

Perhaps, the older ones among you remember the polio epidemic

that occurred in Argentina in 1956.

發生了一場小兒麻痺流行病

At that time, there was no vaccine available against polio.

在那時候，沒有適合的疫苗對抗小兒麻痺

People didn't know what to do. They were going crazy.

人們都無計可施

他們都快要被迫瘋了

They would go painting trees with caustic lime.

他們用生石灰畫樹

They'd put little bags of camphor

他們將小包的樟腦放進小孩的內衣褲裡

in their children's underwear, as if that could do something.

彷彿可以產生一些作用

在這場小兒麻痺流行病中

During the polio epidemic, thousands of people died.

And thousands of people were left with very significant neurological damage.

有幾千人死亡

另外有數千人患有影響非常大的神經損害後遺症

I know this because I read about it,

我是因為閱讀而知道這事件的

因為感激疫苗的出現

because thanks to vaccines, my generation was lucky

我們這世代很幸運

不用經歷像那樣恐怖的流行病

to not live through an epidemic as terrible as this.

Vaccines are one of the great successes of the 20th century's public health.

疫苗是20世紀公眾健康

其中一個很大的成就

After potable water,

自從有了可飲用的水

they are the interventions that have most reduced mortality,

對降低死亡率有很大的幫助

even more than antibiotics.

甚至比抗生素還大

Vaccines eradicated terrible diseases such as smallpox from the planet

疲苗杜絕地球上很多可怕的疾病

例如天花

更成功大大地降低

and succeeded in significantly reducing mortality

due to other diseases such as measles,

因其他疾病造成的死亡率，例如麻疹

whooping cough, polio and many more.

百日咳、小兒麻痺，還有更多

All these diseases are considered vaccine-preventable diseases.

以上所有疾病都被視為

疫苗可預防疾病

What does this mean?

這是甚麼意思呢？

That they are potentially preventable,

即是它們是可預防的

but in order to be so, something must be done.

但要預防，必需做一點東西

You need to get vaccinated.

你需要接種疫苗

我經常想，如果今天我們都不在這兒

I imagine that most, if not all of us here today,

received a vaccine at some point in our life.

在我們人生中某個時候接種疫苗

現在，我不確定

Now, I'm not so sure that many of us know

我們當中多少人知道長大成人後

which vaccines or boosters we should receive after adolescence.

應該接受哪上疫苗或增壓劑

Have you ever wondered who we are protecting

你有沒有曾經想過當我們接種疫苗時

when we vaccinate?

我們正在保護誰？

What do I mean by that?

我究竟想帶出甚麼意思？

Is there any other effect beyond protecting ourselves?

除了保護我們自身

有沒有帶來其他影響？

讓我告訴你一些事

Let me show you something.

Imagine for a moment

試想像現在這一刻

我們身處在一個城市裡

that we are in a city

那裡從沒有發生任何一種疾病

that has never had a case of a particular disease,

such as the measles.

譬如麻疹

This would mean that no one in the city has ever had contact with the disease.

即是說在城市裡

無一曾經和疾病扯上關係

無一擁有天然防禦力能

No one has natural defenses against, nor been vaccinated against measles.

或者曾接種疫苗對抗麻疹

假若有一天，這個城市出現麻疹

If one day, a person sick with the measles appears in this city

有一個人染了病

the disease won't find much resistance

這個疾病的抗性不高

and will begin spreading from person to person,

它會開始人傳人

and in no time it will disseminate throughout the community.

而且很快就會廣泛地傳播到整個社區

After a certain time

在一段時間之後

a big part of the population will be ill.

很大部分的人都會染病

This happened when there were no vaccines.

這種情形是發生在還沒有疫苗的時候

Now, imagine the complete opposite case.

現在，想像一下完全相反的情況

We are in a city

我們身處在一個城市

where more than 90 percent of the population

那兒有超過9成人口對麻疹是有防禦能力的

has defenses against the measles, which means

意思即是要不他們是曾經患有麻疹，幸而存活

that they either had the disease, survived, and developed natural defenses;

有了自然的抵抗力

or that they had been immunized against measles.

要不就是他們本身就已經對麻疹免疫

假如有一天

If one day,

a person sick with the measles appears in this city,

城裡有一個人罹患麻疹

the disease will find much more resistance

疾病的抗性較高

and won't be transmitted that much from person to person.

不會那麼容易在人與人之間傳播

The spread will probably remain contained

病情就可以受到控制

and a measles outbreak won't happen.

麻疹的爆發亦不會發生

我想請你們注意一點

I would like you to pay attention to something.

People who are vaccinated

已接種疫苗的人

are not only protecting themselves,

不單止保障了他們自身

更加阻止了疾病在社區內散播

but by blocking the dissemination of the disease

within the community,

他們間接保障了

they are indirectly protecting the people in this community

社區裡的未接種疫苗人

who are not vaccinated.

They create a kind of protective shield

他們創造了一個保護屏障

which prevents them from coming in contact with the disease,

來避免疾病闖進接觸到人們

so that these people are protected.

因此那些人受到保障

This indirect protection

這一種由已接種疫苗的人包圍群體內未接種的人

that the unvaccinated people within a community receive

令他們簡單地得到的間接保護

simply by being surrounded by vaccinated people,

is called herd immunity.

叫群體免疫

有很多在社群裡的人

Many people in the community

depend almost exclusively on this herd immunity

幾乎只靠這種群體免疫來對抗疾病

to be protected against disease.

The unvaccinated people you see in infographics are not just hypothetical.

你見到圖像裡未接種疫苗的人不只是個假設

那些人是我們的姪女姪兒、我們的孩子

Those people are our nieces and nephews, our children,

who may be too young to receive their first shots.

他們都可能因為年紀太小 而不能接受首次疫苗注射

那些人或會是我們的父母、兄弟姊妹

They are our parents, our siblings,

our acquaintances,

who may have a disease,

我們認識的人卻患有疾病

or take medication that lowers their defenses.

或者接受了藥劑反而會減低他們的防禦能力

此外還有一些對於某種疫苗會過敏的人

There are also people who are allergic to a particular vaccine.

甚至在我們當中

They could even be among us,

any of us who got vaccinated,

有些人注射了疫苗

but the vaccine didn't produce the expected effect,

但是疫苗達不到預期的效果

因為不是所有疫苗都百分之百有效

because not all vaccines are always 100 percent effective.

All these people depend almost exclusively on herd immunity

這些人全部都幾乎

只靠群體免疫來對抗疾病

to be protected against diseases.

To achieve this effect of herd immunity,

要實現群體免疫的效用

必需要很大的人口比例接種疫苗

it is necessary that a large percentage of the population be vaccinated.

This percentage is called the threshold.

這個比例叫作閾值數

The threshold depends on many variables:

閾值數取決於很多變數

取決於種的特性

It depends on the germ's characteristics,

and those of the immune response that the vaccine generates.

和疫苗產生的免疫反應

但他們都有一個共通點

But they all have something in common.

If the percentage of the population in a vaccinated community

那就是，如果已接種疫苗社區的人口比例

低於這個閾值數

is below this threshold number,

疾病會更自由無礙地擴散

the disease will begin to spread more freely

and may generate an outbreak of this disease within the community.

可能會導致該社區爆發疫症

Even diseases which were at some point controlled may reappear.

即使之前已受控的疾病都可能再出現

This is not just a theory.

這個不止是理論

This has happened, and is still happening.

是有發生過，而且仍然在發生

在1998年，一個英國研究者於其中一本

In 1998, a British researcher published an article

很重要的醫學期刊中刊登了一篇論文

in one of the most important medical journals,

saying that the MMR vaccine,

當中提及專門預防麻疹、腮腺炎及風疹的

麻腮風三聯疫苗跟自閉症有關

which is given for measles, mumps and rubella,

was associated with autism.

This generated an immediate impact.

這產生了即時性的影響

人們開始停止接種疫苗，

People began to stop getting vaccinated, and stopped vaccinating their children.

更不讓他們的孩子接種疫苗

And what happened?

然後結果呢？

The number of people vaccinated,

全世界很多國家接種疫苗的人數 下跌至低於閾值數

in many communities around the world, fell below this threshold.

And there were outbreaks of measles in many cities in the world --

世界各國 — 美國、歐洲都爆發麻疹

in the U.S., in Europe.

Many people got sick.

很多人患病

很多人死於麻疹

People died of measles.

What happened?

之後怎樣呢？

This article also generated a huge stir within the medical community.

那篇論文在醫學界亦牽起了巨大的轟動

許多研究人員開始著手評估這是否屬實

Dozens of researchers began to assess if this was actually true.

不單沒有一個找到麻腮風三聯疫苗與

Not only could no one find

a causal association between MMR and autism at the population level,

人口水平上自閉症的因果關係

but it was also found that this article had incorrect claims.

更加發現那篇論文存在不實的言論

Even more, it was fraudulent.

更甚的是，它是騙人的

是欺詐的

It was fraudulent.

事實上，在2010年該期刊 公開聲明收回那篇論文

In fact, the journal publicly retracted the article in 2010.

One of the main concerns and excuses for not getting vaccinated

其中一個主要的顧慮和不接種疫苗的藉口

are the adverse effects.

是不利的影響

疫苗，就像其他藥物

Vaccines, like other drugs, can have potential adverse effects.

可以帶來潛在的反面影響

Most are mild and temporary.

多數是溫和及短暫的

But the benefits are always greater than possible complications.

但益處一般都比可能存在的併發症多

When we are ill, we want to heal fast.

當我們患病，一定要盡快醫治

許多人當被感染到傳染病時會服食抗生素

Many of us who are here

take antibiotics when we have an infection,

當高血壓時服用降壓藥

we take anti-hypertensives when we have high blood pressure,

有時候服食心臟藥

we take cardiac medications.

為甚麼呢？因為我們生病，需要盡快治理

Why? Because we are sick and we want to heal fast.

And we don't question it much.

我們不會對此存疑

Why is it so difficult to think of preventing diseases,

那為甚麼當我們健康的時候將預防疾病

by taking care of ourselves when we are healthy?

當作是照顧自己一樣就變得這麼困難呢？

在我們患病時或者在危難迫近眉睫的情形時

We take care of ourselves a lot when affected by an illness,

or in situations of imminent danger.

我們懂得好好照顧自己

我想在座各位很多都記得2009年

I imagine most of us here,

remember the influenza-A pandemic

在阿根廷及世界各地爆發的流感大流行

which broke out in 2009 in Argentina and worldwide.

When the first cases began to come to light,

當時第一批感染個案曝光時

we, here in Argentina, were entering the winter season.

我們在阿根廷正在步入冬季

We knew absolutely nothing.

當時我們一無所知

簡直是一團糟

Everything was a mess.

People wore masks on the street, ran into pharmacies to buy alcohol gel.

街上的人們都戴上口罩走到藥房購買酒精液

People would line up in pharmacies to get a vaccine,

人們在藥房外排隊等候疫苗

without even knowing if it was the right vaccine

他們甚至不知道那疫苗是否合適

that would protect them against this new virus.

是否能夠保護他們對抗新病毒

We knew absolutely nothing.

我們完全是一無所知

At that time, in addition to doing my fellowship at the Infant Foundation,

當時，我除了處理我在 嬰幼兒基金會研究金的審查

I worked as a home pediatrician for a prepaid medicine company.

我還在一間預付醫藥公司當家庭兒科醫生

I remember that I started my shift at 8 a.m.,

我記得當時從早上8時當值至晚上8時

and by 8, I already had a list of 50 scheduled visits.

已經有50個預定探訪的名單

那時一片混亂；大家都不知道怎麼辦

It was chaos; people didn't know what to do.

I remember the types of patients that I was examining.

我還記得我很留意為哪些類型的病人作檢查

The patients were a little older than what we were used to seeing in winter,

那些病人比我們往常在冬季見到的年紀大一點

發燒的時間較長一點

with longer fevers.

我向我研究金的導師提及這一點

And I mentioned that to my fellowship mentor,

and he, for his part, had heard the same from a colleague,

他亦從他的同事聽聞過相同的情況

about the large number of pregnant women

大量孕婦及年輕成人正在深切治療部留醫

and young adults

being hospitalized in intensive care,

with hard-to-manage clinical profiles.

他們的臨床資料被歸類為複雜個案

At that time, we set out to understand what was happening.

在那時候，我們著手瞭解究竟發生甚麼事

First thing Monday morning, we took the car

在星期一早上

我們駕車到布宜諾斯艾利斯省的一家醫院

and went to a hospital in Buenos Aires Province,

那兒被劃為新型流感病毒個案的轉診醫院

that served as a referral hospital for cases of the new influenza virus.

我們到達醫院的時候，那兒很擁擠

We arrived at the hospital; it was crowded.

All health staff were dressed in NASA-like bio-safety suits.

所有醫護人員都穿上 像美國太空總署的生物安全服

We all had face masks in our pockets.

我們全部在衣袋裡都有面罩

I, being a hypochondriac, didn't breathe for two hours.

我猶如一個疑病症患者，兩小時都不能呼吸

可是我們目睹這是甚麼一回事

But we could see what was happening.

Immediately, we started reaching out to pediatricians

我們立即開始聯絡位於城市及

布宜諾斯艾利斯省一共六間醫院的兒科醫生

from six hospitals in the city and in Buenos Aires Province.

Our main goal was to find out

我們的主要目的是在最短到時間內找出

how this new virus behaved in contact with our children,

這種新病毒在接觸小孩時有甚麼表現

in the shortest time possible.

A marathon work.

是一場馬拉松式的工作

在三個月內

In less than three months,

我們見到新型H1N1病毒

we could see what effect this new H1N1 virus had

在251個因該病毒而留醫的小朋友身上產生甚麼影響

on the 251 children hospitalized by this virus.

We could see which children got more seriously ill:

我們見到哪些小孩會病得較重：

children under four, especially those less than one year old;

四歲以下，尤其少於一歲的小朋友；

有神經疾病的患者；

patients with neurological diseases;

and young children with chronic pulmonary diseases.

與及患上慢性肺部疾病的小朋友

Identifying these at-risk groups was important

識別這些高危人士很重要

to include them as priority groups

可以將他們囊括在建議 優先取得流感疫苗的一群裡

in the recommendations for getting the influenza vaccine,

not only here in Argentina,

不單只在阿根廷

but also in other countries which the pandemic not yet reached.

在其它流感大流行尚未出現的國家都一樣

A year later,

一年後

when a vaccine against the pandemic H1N1 virus became available,

對抗流感大流行H1N1病毒的疫苗面世

we wanted to see what happened.

我們想見到會發生甚麼事

After a huge vaccination campaign

在一個以保障高危一族為主的 大型疫苗接種活動後

aimed at protecting at-risk groups,

那些醫院有9成3的高危人士接種疫苗

these hospitals, with 93 percent of the at-risk groups vaccinated,

had not hospitalized a single patient

之後他們再沒有需要留醫H1N1流感的單一患者

for the pandemic H1N1 virus.

(Applause)

（拍掌）

In 2009: 251.

2009年：251宗

2010年：0宗

In 2010: zero.

Vaccination is an act of individual responsibility,

接種疫苗是個人責任的表現

but it has a huge collective impact.

卻帶來龐大的集體影響

If I get vaccinated, not only am I protecting myself,

假如我一經接種，我不單只保障自己

but I am also protecting others.

更保障了其他人

Sol had whooping cough.

索爾罹患百日咳

Sol was very young,

索爾還很年幼

and she hadn't yet received her first vaccine against whooping cough.

她不能夠注射首支疫苗來對抗百日咳

I still wonder what would have happened

我仍然在想

如果每一個在索爾身邊的人都已經接種了疫苗

if everyone around Sol had been vaccinated.

會有一個怎麼樣的結果

(Applause)