Why we have virus outbreaks & how we can prevent them | Nathan Wolfe

ネイサン・ウルフのウイルス退治

翻訳: Hideki Kamiya 校正: Takahiro Shimpo

When most people think about the beginnings

大抵の人々はエイズの発生

of AIDS, they're gonna think back to the 1980s.

と言えば1980年代を思い起こします

And certainly, this was the decade in which we discovered AIDS

確かにその10年間にエイズと

and the virus that causes it, HIV.

その原因ウイルスHIVを発見しました

But in fact this virus crossed over into humans many decades before,

でもその何十年も前に人間に入り込んでいます

from chimpanzees, where the virus originated, into humans who hunt these apes.

チンパンジーから狩人に潜り込んだのです

This photo was taken before the Great Depression

この写真は世界恐慌前の

in Brazzaville, Congo.

コンゴ ブラザビルのものです

At this time, there were thousands of individuals,

この時すでに何千もの人々が

we think, that were infected with HIV.

HIVに感染していたのだと思います

So I have a couple of really important questions for you.

ここで2,3 重大な質問があります

If this virus was in thousands

何千もの人々が

of individuals at this point,

この時点で感染していたのなら

why was it the case that it took us until 1984

なぜこのウイルスを発見するのに

to be able to discover this virus?

1984年までかかったのでしょうか

OK now, more importantly,

次はもっと重要です

had we been there in the '40s and '50s, '60s,

もし我々が1940−60年代に存在し

had we seen this disease, had we understood

この病気を目撃し、正確に状況を

exactly what was going on with it, how might that have changed and completely

理解していたなら、感染性質を変え

transformed the nature of the way this pandemic moved?

全く別のものにできる方法があったのでしょうか

In fact, this is not unique to HIV. The vast majority of

これはHIVに限ったことではありません

viruses come from animals.

ウイルスの多くは動物由来です

And you can kind of think of this as a pyramid of this bubbling up of viruses

動物から人間へと感染するウイルスの

from animals into human populations.

ピラミッドと考えてもいいでしょう

But only at the very top of this pyramid do these things become completely human.

その頂点で完全にヒトウイルスとなります

Nevertheless, we spend the vast majority

ほとんどのエネルギーを費やすのは

of our energy focused on this level of the pyramid,

ピラミッドのこの階層です

trying to tackle things that are already completely adapted to human beings,

人間に完全に適応し解明が非常に困難な

that are going to be very very difficult to address --

ウイルスを研究しています

as we've seen in the case of HIV.

HIVの例でおわかりでしょう

So during the last 15 years,

ここ15年間

I've been working to actually study the earlier interface here --

初期段階の感染方法を研究してきました

what I've labeled "viral chatter," which was a term coined

「ウイルスのお喋り」は

by my mentor Don Burke.

恩師ドン・バークの造語です

This is the idea that we can study the sort of

この考えは

pinging of these viruses into human populations,

人間社会にウイルスをわざと投げ込み

the movement of these agents over into humans;

その動きを研究し

and by capturing this moment,

感染の瞬間を捉え

we might be able to move to a situation where we can catch them early.

ウイルスを早期発見できるかもしれないというものです

OK, so this is a picture, and I'm going to show you

これがその写真です

some pictures now from the field.

現場の写真です

This is a picture of a central African hunter.

中央アフリカの狩猟者です

It's actually a fairly common picture.

ごく普通の写真に見えます

One of the things I want you to note from it

１つ注意すべき点は

is blood -- that you see a tremendous amount of blood contact.

おびただしい血液接触です

This was absolutely key for us. This is a

これが決定的な鍵です

very intimate form of connection.

非常に直接的な接触です

So if we're going to study viral chatter, we need to

ウイルスのお喋りを調査するなら

get to these populations who have intensive contact with wild animals.

野生動物と接触する住民を探る必要があります

And so we've been studying people like this individual.

我々はこの方のような人々を調査してきています

We collect blood from them, other specimens.

血液や他の検体を採取します

We look at the diseases, which are in the animals as well as the humans.

人以外に動物の病気も調べます

And ideally, this is going to allow us to catch these things

これにより動物ウイルスが人間に侵入した際

early on, as they're moving over into human populations.

初期段階で捕えることが可能なのです

And the basic objective of this work is not to just

この研究の基本目的は

go out once and look at these individuals,

1回きりの調査ではなく

but to establish thousands of individuals

数千人の被験者を選び

in these populations that we would monitor

定期的に継続して

continuously on a regular basis.

観察することです

When they were sick, we would collect specimens from them.

病気なら検体を採取します

We would actually enlist them --

今進行中ですが協力を得て

which we've done now -- to collect specimens from animals.

動物の検体を採取します

We give them these little pieces of filter paper.

このような小さなろ紙を渡し

When they sample from animals,

動物の標本採取の際

they collect the blood on the filter paper

ろ紙に血液を取ります

and this allows us to identify yet-unknown viruses from exactly the right animals --

こうして対象動物から未確認ウイルスを発見します

the ones that are actually being hunted.

実際に狩猟されている動物からです

(Video) Narrator: Deep in a remote region of Cameroon,

（ビデオ）語り手：カメルーンの人里離れた山奥で

two hunters stalk their prey.

2人の狩猟者が獲物に忍び寄ります

Their names are Patrice and Patee.

パトリスとパティです

They're searching for bush meat;

家族のために食用肉となる

forest animals they can kill to feed their families.

森林動物を探しています

Patrice and Patee set out most days to go out hunting

家の近くの森に

in the forest around their homes.

ほぼ毎日狩りに出かけます

They have a series of traps, of snares that they've set up

わなを仕掛け

to catch wild pigs, snakes, monkeys,

ブタ、ヘビ、サル

rodents -- anything they can, really.

ネズミ等を捕獲します

Patrice and Patee have been out for hours but found nothing.

この日は何時間も探しましたが、収穫はありませんでした

The animals are simply gone.

動物がいないのです

We stop for a drink of water.

水を飲もうと立ち止ります

Then there is a rustle in the brush.

するとやぶからサラサラと音が聞こえます

A group of hunters approach,

狩猟者がそこに近づきます

their packs loaded with wild game.

なんと獲物でいっぱいです

There's at least three viruses

このサルには少なくとも

that you know about, which are in this particular monkey.

3種類の既知ウイルスがいます

Nathan Wolfe: This species, yeah. And there's many many more pathogens

ネイサン・ウルフ：この動物にはかなり多くの

that are present in these animals.

病原体が存在します

These individuals are at specific risk,

この狩猟者たちは危険な状態です

particularly if there's blood contact, they're at risk for transmission

特にもし血液接触があれば

and possibly infection with novel viruses.

新種ウイルス感染の危険もあります

Narrator: As the hunters display their kills, something surprising happens.

獲物を誇示する際驚くべき事実が判明します

They show us filter paper they've used to collect the animals' blood.

動物の血液採取のろ紙を見せてくれます

The blood will be tested for zoonotic viruses,

血液は人畜共通性感染ウイルス陽性で

part of a program Dr. Wolfe has spent years setting up.

博士が何年も探し求めているものです

NW: So this is from this animal right here,

これはここにいる動物

Greater Spot-Nosed Guenon.

大鼻オナガザルのものです

Every person who has one of those filter papers has at least,

どのろ紙の使用者も

at a minimum, been through our basic health education

最低限の基礎健康教育を受けています

about the risks associated with these activities,

この研究の危険性についての教育で

which presumably, from our perspective,

それは我々の観点から見れば

gives them the ability to decrease their own risk,

自らの危険だけではなく

and then obviously the risk to their families,

明らかに家族や

the village, the country, and the world.

村、国、世界に対する危険を減少させるものです

NW: OK, before I continue, I think it's important to take just a moment

先に進む前に食用肉の話を少しします

to talk about bush meat. Bush meat is the hunting of wild game.

食用肉は野生鳥獣の獲物です

OK? And you can consider all sorts of different bush meat.

様々な食用肉が考えられます

I'm going to be talking about this.

それについてお話しましょう

When your children and grandchildren

子供や孫がこの賞味期限

sort of pose questions to you about this period of time,

について質問をする際

one of the things they're gonna ask you,

その1つはこうです

is how it was they we allowed some of our closest living relatives,

人間に最も近い生物

some of the most valuable and endangered species

最も貴重な絶滅危惧種が

on our planet, to go extinct because we

なぜ絶滅したのか

weren't able to address some of the issues

これらの地域で貧困問題に

of poverty in these parts of the world.

取り組まなかったからなのか

But in fact that's not the only question they're going to ask you about this.

でもそれが唯一の質問ではありません

They're also going to ask you the question

こういう質問もします

that when we knew that this was the way that HIV entered

このようにしてHIVが

into the human population,

人間社会に入り込み

and that other diseases had the potential to enter like this,

他の病気の潜在性を知っていたのなら

why did we let these behaviors continue?

なぜ放っておいたのか

Why did we not find some other solution to this?

解決法を見つけなかったのか

They're going to say, in regions of profound

きっとこう言います。世界中の

instability throughout the world,

生活不安定な地域では

where you have intense poverty, where populations are growing

厳しい貧困、人口増大、持続可能な資源

and you don't have sustainable resources like this,

の欠乏に苦しんでおり

this is going to lead to food insecurity.

今の状態では食料不足になります

But they're also going to ask you probably a different question.

しかし別の質問もあるでしょう

It's one that I think we all need to ask ourselves,

我々は皆自問する必要があります

which is, why we thought the responsibility rested with this individual here.

なぜこの狩猟者に責任があると思うのか、です

Now this is the individual -- you can see just right up over his right shoulder --

狩猟者です。右肩越しに見えますね

this is the individual that hunted the monkey

最後にお見せした写真の

from the last picture that I showed you.

サルを捕まえた狩猟者です

OK, take a look at his shirt.

シャツを見てください

You know, take a look at his face.

顔も見てください

Bush meat is one of the central crises,

食用肉は最大危機の1つで

which is occurring in our population right now,

今まさに進行中です

in humanity, on this planet.

地球上の人間社会で

But it can't be the fault of somebody like this.

でもこのように誰かの責任ではありません

OK? And solving it cannot be his responsibility alone.

解決するのも誰か1人だけの問題ではありません

There's no easy solutions,

簡単な解決策はありませんが

but what I'm saying to you is that we neglect this problem

我々はこの問題を放置して

at our own peril.

自らを危険にさらしているのです

So, in 1998, along with my mentors

1998年に恩師ドン・バークと

Don Burke and Colonel Mpoudi-Ngole,

ムポーディ・ヌゴーリ大佐と共に

we went to actually start this work

この研究を始めるために

in Central Africa, to work with hunters

中央アフリカに行き

in this part of the world.

狩猟者と行動しました

And my job -- at that time I was a post-doctoral fellow,

私は当時博士研究員で

and I was really tasked with setting this up.

この研究の準備を任せられました

So I said to myself, "OK, great --

心の中で誓いました

we're gonna collect all kinds of specimens. We're gonna go to all these

「全標本を採集するぞ

different locations. It's going to be wonderful."

どこでも行ってやる。最高だ」

You know, I looked at the map; I picked out 17 sites;

地図で17ヵ所選びました

I figured, no problem.

問題ないと思ったんですよ

(Laughter)

（笑）

Needless to say, I was drastically wrong.

もちろん全く勘違いです

This is challenging work to do.

これは大変な仕事です

Fortunately, I had and continue to have

幸い、私のチームには

an absolutely wonderful team of colleagues and collaborators in my own team,

最高の同僚と協力者がおり

and that's the only way that this work can really occur.

だからこそ研究が可能なのです

We have a whole range of challenges about this work.

この研究には様々な困難があります

One of them is just obtaining trust

1つは行動を共にする

from individuals that we work with in the field.

狩猟者から信頼を得ることです

The person you see on the right hand side is Paul DeLong-Minutu.

右の方はポール・デロング＝ミヌテュ氏です

He's one of the best communicators that I've really ever dealt with.

最高のコミュニケーターです

When I arrived I didn't speak a word of French,

当時私のフランス語力は０でした

and I still seemed to understand what it was he was saying.

でも言うことがわかる気がしました

Paul worked for years

ポールは何年もの間

on the Cameroonian national radio and television,

カメルーンのラジオやテレビで働き

and he spoke about health issues. He was a health correspondent.

健康問題に詳しい助言者でした

So we figured we'd hire this person -- when we got there he could

彼を雇えば、現地に到着したとき

be a great communicator.

橋渡し役になると考えました

When we would get to these rural villages, though, what we found out

でもこの田舎村に到着すると

is that no one had television,

なんとテレビがないのです

so they wouldn't recognize his face.

だから彼の顔がわかりません

But -- when he began to speak

しかし彼が話し始めると

they would actually recognize his voice from the radio.

ラジオの声でわかったのです

And this was somebody who had incredible

我々のメッセージを伝えてくれる

potential to spread aspects of our message,

可能性のある人物でした

whether it be with regards to wildlife conservation

野生生物保護であろうと

or health prevention.

健康予防であろうとです

Often we run into obstacles. This is us coming back from

障害にもよく遭います

one of these very rural sites,

これは調査地から帰路で

with specimens from 200 individuals

200人の検体を運んでおり

that we needed to get back to the lab within 48 hours.

48時間以内に研究室直行です

I like to show this shot -- this is

これをご覧下さい

Ubald Tamoufe, who's the lead

ウーボルド・タムーフィで

investigator in our Cameroon site.

カメルーンでの調査主任です

Ubald laughs at me when I show this photo

この写真を見せると笑います

because of course you can't see his face.

顔が見えないからです

But the reason I like to show the shot

しかしお見せする理由は

is because you can see that he's about to solve this problem.

彼がこの問題を解決しようとしているからです

(Laughter)

（笑）

Which -- which he did, which he did.

実際に解決したんですよ。本当に

Just a few quick before and after shots.

過去と今の写真を紹介します

This was our laboratory before.

以前の研究所です

This is what it looks like now.

これが現在の外観です

Early on, in order to ship our specimens,

以前は検体を送るのに

we had to have dry ice. To get dry ice we had to go

ドライアイスが必要で醸造所で

to the breweries -- beg, borrow, steal to get these folks to give it to us.

人に頼んで何とか入手していました

Now we have our own liquid nitrogen.

今は液体窒素を持参します

I like to call our laboratory the coldest place in Central Africa -- it might be.

研究所は中央アフリカ一寒い所かもしれません

And here's a shot of me, this is the before shot of me.

私の写真です。以前の写真です

(Laughter)

（笑）

No comment.

ノーコメントです

So what happened? So during the 10 years that we've been doing

現状は、この10年間

this work, we actually surprised ourselves.

研究をしてきて、驚いています

We made a number of discoveries.

多くの発見をしました

And what we've found is that if you look in the right place,

適切な場所を調査すれば

you can actually monitor the flow

ウイルスが侵入する様子を

of these viruses into human populations.

捉えることができるのです

That gave us a tremendous amount of hope.

非常に大きな希望の光です

What we've found is a whole range of new viruses in these individuals,

発見したのは住人体内の新種ウイルスです

including new viruses in the same group

HIVと同じグループのものを含む

as HIV -- so, brand new retroviruses.

新種レトロウイルスです

And let's face it, any new retrovirus in the

現実を見て、人間社会の

human population -- it's something we should be aware of.

新種レトロウイルスを全て識別するべきです

It's something we should be following. It's not something

我々はそれを探し求めているのです

that we should be surprised by.

驚くことはありません

Needless to say in the past

勿論過去にこの農村地域に

these viruses entering into these rural communities

侵入したウイルスは

might very well have gone extinct.

絶滅しているかもしれません

That's no longer the case. Logging roads provide access to urban areas.

今は違います。道路が都市への通路となります

And critically, what happens in central Africa

危険なことに中央アフリカの状況は

doesn't stay in Central Africa.

その地域だけにとどまりません

So, once we discovered that it was really possible

このウイルス監視が

that we could actually do this monitoring,

可能だとわかると

we decided to move this from research, to

研究を更に拡張し

really attempt to phase up to a global monitoring effort.

全世界の監視体制確立を決めました

Through generous support and partnership

グーグル及びスコール財団からの

scientifically with Google.org and the Skoll Foundation,

手厚いご支援と科学的提携により

we were able to start the Global Viral Forecasting Initiative

グローバルウイルス予測計画を立ち上げ

and begin work in four different sites

アフリカとアジアの

in Africa and Asia.

4地点で研究を始めました

Needless to say, different populations from different parts of the world

勿論ウイルスとの接触過程は

have different sorts of contact.

住民によってそれぞれ異なります

So it's not just hunters in Central Africa.

中央アフリカの狩猟者というだけではなく

It's also working in live animal markets --

野生動物市場等でも見られます

these wet markets -- which is exactly the place where

湿地帯市場で活動しており

SARS emerged in Asia.

アジアにて発祥した所です

But really, this is just the beginning from our perspective.

でも研究計画の単なる始まりです

Our objective right now, in addition to

現時点の目的は

deploying to these sites and getting everything moving,

人員を配置し、研究を開始して

is to identify new partners

新たな協力者を得ることです

because we feel like this effort needs to be extended

世界の20以上のウイルスの温床に

to probably 20 or more sites throughout the world -- to viral hotspots --

研究を拡張する必要性を感じているからです

because really the idea here is to cast an incredibly wide net

この考えは途方もなく広い網を投げ

so that we can catch these things, ideally,

理想的にはウイルスを捕えることです

before they make it to blood banks,

血液バンク、性生活

sexual networks, airplanes. And that's really our objective.

航空機への侵入を未然に防ぐのが目的です

There was a time not very long ago

少し前の時代には

when the discovery of unknown organisms

未確認生物の発見に

was something that held incredible awe for us.

畏怖を感じた時がありました

It had potential to really change the way that we saw ourselves,

我々自身の見方や考え方を変える

and thought about ourselves.

可能性があったということです

Many people, I think, on our planet right now

多くの人々が今地球上で

despair, and they think

絶望して人間はもうほとんどの事象を

we've reached a point where we've discovered most of the things.

発見してしまったと考えます

I'm going tell you right now: please don't despair.

絶望することはありません

If an intelligent extra-terrestrial

もし知的地球外生命体が

was taxed with writing the encyclopedia of life on our planet,

生物百科事典を編纂するなら

27 out of 30 of these volumes

全30巻のうち27巻が

would be devoted to bacteria and virus,

細菌とウイルスに割かれ

with just a few of the volumes left

残りの数少ない部分が

for plants, fungus and animals,

植物や菌類、動物です

humans being a footnote;

人間は脚注扱いで

interesting footnote but a footnote nonetheless.

興味深いですが、でも所詮脚注です

This is honestly the most exciting period

現在は地球上の未確認生命体の

ever for the study of unknown life forms on our planet.

研究にとって最も躍動的な時です

The dominant things that exist here

地上で優位な存在でも

we know almost nothing about.

未解明の生命体も存在します

And yet finally, we have the tools, which will allow us to actually explore that world

しかし素晴らしい手段を手に入れ

and understand them.

未知の世界の探究理解が可能となるのです

Thank you very much.

ご清聴ありがとうございました

(Applause)

（拍手）