In many patients, the pill helped.

這個藥丸在許多病人身上看到了效果。

But in seven of them, just a few days into the treatment, researchers found mutated virus variants that were almost completely resistant to pleconaril.

但在其中 7 位病人中，研究人員在他們接受治療的幾天後發現了幾乎完全抵抗 pleconaril 的突變病毒的突變體。

The viruses are always mutating, but this one mutated so quickly that it managed to outmaneuver years of research and development in just a few days.

病毒總是在變異，但這個病毒變異得非常之快，快到它在短短幾天內就戰勝了多年的藥物研究和開發。

If you didn't have an immune system and caught a cold, the infection would quickly spread deep into your lungs.

如果你本身沒有免疫系統並且感冒了，感染會迅速擴散到你的肺部深處。

Rampant viral replication would destroy tissue there, until your lungs couldn't supply your body with enough oxygen and you'd asphyxiate.

猖獗的病毒複製會破壞該器官的組織，直到你的肺不能為你的身體提供足夠的氧氣，最後你會窒息。

Unfortunately, for millions of people around the world who live with a less-than-fully-functional immune system or who are on immunosuppressant drugs, this is a real risk,

不幸的是，對於全世界數百萬免疫系統功能不全或正在服用免疫抑製藥物的人來說，這真的是一個風險，

quote unquote "minor" infections can turn serious or even deadly.

因為就算是「輕微」的感染也可以變得很危險，甚至是致命。

But if you're fortunate enough to have a fully functional immune system, a cold will probably give you a few relatively mild symptoms.

但是，如果你夠幸運，擁有功能完備的免疫系統，那麼感冒可能會給你帶來一些相對輕微的症狀。

On average, adults catch more than 150 colds throughout their lives.

平均而言，成年人一生中會得到 150 多次感冒。

And despite the fact that the symptoms are similar, the cause could be different each time.

儘管症狀相似，但每次的原因都可能不同。

Common colds are caused by at least eight different families of virus, each of which can have its own species and subtypes.

普通感冒是由至少八個不同的病毒種類引起的，每種病毒都有自己的種類和亞型。

How can so many different viruses cause the same illness?

為什麼這麼多不同種類的病毒會造成相同的疾病呢。

Well, viruses can only invade our bodies in a few ways, one is to come in on a breath,

這是因為，病毒只能透過幾種方式侵入我們體內，其中一種是透過呼吸，

and we have to breathe, so our immune system sets up a bunch of frontline defenses and these are actually what produce many of the symptoms of a cold.

而我們勢必得呼吸，所以我們的免疫系統建立了一堆前線防禦，而這些其實是產生許多感冒症狀的原因。

Your mucusy, dripping nose is your immune system trapping and flushing out virus.

流鼻水的症狀就是免疫系統捕獲和沖洗掉病毒的表現。

Your fever is your immune system raising your body temperature to slow down viral replication.

發燒是免疫系統提高身體溫度以減緩病毒複製的表現。

And your inflamed, well, everything, that's your immune system widening your blood vessels and recruiting its white blood cell army to help kill the virus.

而發炎都是免疫系統擴大了血管並聚集白細胞軍隊來幫助殺死病毒。

So, if the common cold is caused by many different viruses, is a cure even possible?

那麼，如果普通感冒是由許多不同的病毒引起的，是否有可能治愈呢？

Here's one fact in our favor: a single family of viruses causes 30 to 50% of all colds: rhinovirus.

有一個真實狀況對我們是有利，有一個病毒家族會導致全部感冒的 30% 到 50% ，也就是鼻病毒。

If we could eliminate all rhinovirus infections, we'd be a long way towards curing the common cold.

如果我們能夠消除所有的鼻病毒感染，那麼我們在治愈普通感冒方面還有很長的路要走。

There are two main ways to fight a virus: vaccines and antiviral drugs.

對抗病毒的方法主要有兩種：疫苗和抗病毒藥物。

The first attempt to create a rhinovirus vaccine was a success, but a short-lived one.

第一次嘗試研製鼻病毒疫苗取得了成功，但卻是曇花一現。

In 1957, William Price vaccinated 50 kids with inactivated rhinovirus and gave 50 others a placebo.

1957 年，William Price 為 50 名兒童接種了滅絕鼻病毒的疫苗，並給另外 50 名兒童注射了安慰劑。

Soon afterwards, a rhinovirus outbreak spread throughout the kids.

不久之後，一場鼻病毒在孩子們中爆發開來。

In the vaccinated group, only three got sick.

在有接種疫苗的那群人中，只有三人生病。

In the placebo group, 23 did — almost eight times as many.

在施打安慰劑的人中，有 23 人生病，是注射疫苗組的八倍。

And despite the small numbers, this was promising.

儘管研究的數量很少，但還是有希望的。

The immune systems of vaccinated kids were successfully recognizing and responding to rhinovirus.

接種疫苗的兒童的免疫系統成功識別鼻病毒並對其做出反應。

But later trials of the vaccine showed no protection at all, none.

但是後來對該疫苗的試驗表明疫苗根本沒有保護作用，完全沒有。

This wasn't Price's fault. No one at the time knew that rhinovirus had multiple subtypes.

這不是 Price 的錯，畢竟當時沒有人知道鼻病毒會有很多種亞型。

Price's vaccine, for reasons we don't fully understand, didn't provide broad protection,

由於我們不完全了解的原因，Price 的疫苗沒有提供廣泛的保護作用，

meaning it was only effective against one or maybe a few subtypes of rhinovirus — out of 169 subtypes and counting.

這表示，在 169 種並且還在增加的亞型中，疫苗僅對鼻病毒的其中一種或幾種亞型有效。

Sometimes, when we make a vaccine, we get lucky.

有時，當我們製造疫苗時，我們很幸運。

The mRNA COVID vaccines, for example, effectively protect us against severe disease and death across the original virus and variants too.

例如，mRNA 的新冠疫苗也有效地保護我們免受原始病毒和變種嚴重疾病和死亡。

But we have yet to create a broadly protective vaccine against rhinovirus, or any other virus that causes the common cold.

但是我們還沒有研製出一種針對鼻病毒或任何其他引起普通感冒的病毒具有廣泛保護作用的疫苗。

Okay, what about antiviral drugs?

那抗病毒藥物呢？

Viruses hijack human cellular machinery to replicate and spread, so it's hard to make a molecule that's toxic to the virus without also being toxic to the human.

病毒控制人體細胞進行複制和傳播的機制，因此很難製造出對病毒有毒而又對人體無毒的分子。

And even if you manage to do that, the virus could mutate out of reach of the drug.

即使設法做到了，病毒也可能會發生變異，超出藥物的範圍。

Viruses are slippery beasts.

病毒是狡猾的野獸。

We have, though, had some incredible successes.

不過，我們還是取得了一些令人難以置信的成功。

We eradicated smallpox thanks to an effective vaccine, the fact that it can't hide out in other species, and its relatively low mutation rate.

得益於有效的疫苗、天花無法隱藏在其他物種中以及相對較低的突變率，我們根除了天花。

HIV, on the other hand, mutates so quickly that in an untreated individual, every possible single-letter mutation in the virus's genetic code could, in theory, be produced in a single day.

另一方面，HIV 變異速度之快，以至於在未經治療的個體中，理論上，病毒的基因中的每一個可能的單字母突變都可以在一天內產生。

Despite trying for decades, we still don't have a vaccine.

儘管嘗試了幾十年，我們仍然沒有做出有效的疫苗。

But we do have an effective cocktail of HIV drugs that the virus can't easily mutate away from.

但我們確實有一種有效的 HIV 藥物混合物是病毒無法輕易變異的。

Unfortunately, we are stuck with colds for now.

不幸的是，我們現在還是被感冒困擾著。

But the last few decades have featured some entirely game-changing medical breakthroughs, like mRNA vaccines and CRISPR.

但過去幾十年出現了一些完全改變遊戲規則的醫學突破，例如 mRNA 疫苗和 CRISPR。

CRISPR could be particularly promising as an antiviral agent, because it originally evolved in bacteria as an immune defense against viruses.

CRISPR 作為一種抗病毒劑可能特別有希望，因為它最初是由細菌進化的，作為一種針對病毒的免疫防禦。

In fact, early in the COVID-19 pandemic, a research team showed that a CRISPR system could degrade coronavirus and influenza genomes in our lung cells.

事實上，在新冠疫情初期，一個研究小組表明，CRISPR 系統可以降解我們肺細胞中的冠狀病毒和流感基因組。

They called their system prophylactic antiviral CRISPR in human cells, or, for short, PAC-MAN.

他們將其系統稱為人類細胞中的預防性抗病毒 CRISPR，或簡稱為 PAC-MAN。（PAC-MAN 是小精靈的英文名稱）