Seminar Presentation: How Vaccines Train Your Immune System

Right, let's begin. Priya, the floor is yours.

好，我們開始吧。Priya，換你了。

Thanks. Um, I'm a bit nervous, so bear with me.

謝謝。嗯，我有點緊張，請大家多包涵。

Today I'm going to explain how vaccines actually work.

今天我要說明疫苗到底是怎麼發揮作用的。

So, have you ever done a fire drill at school?

那麼，你們在學校做過消防演習嗎？

Ha, loads of times. Usually in the rain.

哈，好多次了。而且常常是下雨天。

Exactly! Nobody's in danger, but everyone practises.

沒錯！沒有人有危險，但每個人都在練習。

Well, a vaccine is basically a fire drill for your body!

其實，疫苗基本上就是給身體做的一場消防演習！

Every germ carries tiny markers called antigens.

每種病菌身上都帶有一種叫抗原的微小標記。

A vaccine shows your body those markers,

疫苗會把這些標記展示給你的身體，

using a weakened germ, a dead one, or just a piece of it.

用的是減弱的病菌、不活化的病菌，或者只是它的一小部分。

So you get the practice, without the real illness.

這樣你就能練習，卻不必真的生病。

And then, your immune system gets to work!

接著，你的免疫系統就開始工作了！

It makes antibodies that stick to the antigens,

它會製造能附著在抗原上的抗體，

and it creates something brilliant: memory cells!

還會產生一樣很厲害的東西：記憶細胞！

If the real germ turns up later, they recognise it fast.

以後真正的病菌一出現，它們很快就能認出來。

Your body fights back before you even feel ill!

你還沒覺得不舒服，身體就已經反擊了！

Sorry, can I ask something?

不好意思，我可以問個問題嗎？

Of course, go ahead.

當然，你問吧。

If memory cells last, why do we need boosters?

如果記憶細胞會一直在，為什麼還要打追加劑？

Honestly, why do I need a flu jab every single year?

說真的，為什麼我每年都得打流感疫苗？

Hmm... good question. Let me think.

嗯……好問題。讓我想一下。

Well, for some vaccines, the memory slowly fades.

嗯，有些疫苗留下的記憶會慢慢變淡。

A booster is just a reminder for your immune system.

追加劑只是幫免疫系統提個醒。

And flu viruses change their antigens all the time.

而且流感病毒老是在改變它們的抗原。

So last year's practice doesn't match this year's flu.

所以去年的演習對不上今年的流感。

Oh, that actually makes sense!

喔，這樣說還真有道理！

One last point: herd immunity.

最後一點：群體免疫。

When most people are protected, the germ can't spread easily.

當大多數人都受到保護時，病菌就不容易傳播。

That protects newborn babies, and people who can't have vaccines.

這能保護新生兒，還有無法接種疫苗的人。

So, that's it! Thank you for listening.

好，就是這樣！謝謝大家聆聽。

Excellent, Priya! The fire drill idea worked really well.

太棒了，Priya！消防演習的比喻用得非常好。

Just slow down a little at the start.

只是開頭的時候稍微放慢一點。

Oh, thank you! Honestly, I was terrified.

喔，謝謝！老實說，我剛剛超怕的。

You didn't look it. Well done!

完全看不出來。講得好！