And if you're the kind of person who seems to be eaten alive every time you step outside,

如果你是那種每次走出戶外就好像會被活活吃掉的人，

you might have wondered if there's some way you could become immune to their bites.

你可能已經想過，是否有可以讓你對蚊子叮咬免疫的某種方法。

Well, I have some good news.

嗯，我有一些好消息。

You probably can, because mosquito bites are just a kind of allergic reaction.

大概可以，因為蚊子叮咬只是一種過敏反應。

But, like any allergy, the only way to become desensitized is with repeated exposure.

但是像任何過敏症一樣，脫敏的唯一途徑是反覆接觸。

And I'm not talking about a few bites.

我在說的不是只叮咬幾口而已。

I'm talking about thousands of them over months.

我是說，接連數月地被叮咬成千上萬次。

When a mosquito bites, she injects you with a chemical cocktail that helps numb the area and keeps your delicious blood flowing.

當蚊子叮咬時，牠會在你體內注入一種化學雞尾酒，用以幫助麻痺該區域並讓你美味的血液繼續流動。

The chemicals themselves don't cause the redness, swelling, or itching, though.

不過，這些化學物質本身並不會導致紅、腫或瘙癢。

Your immune system's overreaction to them does.

是你免疫系統對它們的過度反應作祟。

Which is why mosquito bites are considered a kind of mild allergic reaction.

這就是蚊子叮咬被認為是一種溫和過敏反應的原因。

Your immune system learns to recognize these proteins as foreign,

你的免疫系統學會將這些蛋白質辨識為異物，

and it primes specialized cells so the next time you're bitten, your body can launch a rapid immune attack.

它會替專門的細胞做好準備，好讓你在下次被叮咬時，身體可以快速發起免疫攻擊。

This is what's known as sensitization.

這就是所謂的敏化。

Specifically, mosquito proteins tend to activate the production of two kinds of immune weapons: IgE and IgG antibodies.

具體來說，蚊子的蛋白質傾向於激發兩種免疫武器的生產：IgE 和 IgG 抗體。

When these antibodies bind to mosquito proteins, they ramp up the release of the molecule histamine,

當這些抗體與蚊子蛋白質結合時，它們會加速釋放分子組胺，

and, ultimately, that causes those wonderful itchy bumps.

最終導致那些奇癢無比的腫塊。

These antibodies can also cause much worse allergic symptoms, though, including full-on anaphylaxis.

不過，這些抗體也可能引起更嚴重的過敏症狀，包括嚴重的過敏性休克。

Exactly why severe reactions happen in some people and not others is something doctors are still trying to figure out.

嚴重的反應究竟為什麼發生在一些人身上，而其他人身上不會有，是醫生仍在試圖釐清的事情。

But what we do know is that, for the most part, if you can become sensitized to something, you can also become desensitized to it.

但我們所知道的是，在多數情況下，如果你能對某種東西敏化，那也可以對它脱敏。

The trick is to induce your allergic response so frequently that you end up convincing your body that reacting is a waste of energy.

訣竅是頻繁地誘發你的過敏反應，讓你最終說服你的身體，對它起反應是一種能量的浪費。

That's the basic principle behind allergy shots, also called specific immunotherapy.

這就是注射過敏疫苗的基本原則，也稱為特定免疫療法。

Doctors have developed standard protocols for allergens like pet dander and pollen.

醫生們已經為寵物皮屑和花粉等過敏原制定了標準方案。

But we know the same idea works with mosquito bites, too.

但我們知道這個想法對蚊子叮咬也很有效。

For example, the older you are and the longer you live in the same place, the less your reaction to bites from local mosquito species tends to be.

例如，你年齡越大、在同一個地方居住的時間越長，對當地蚊子種類的叮咬反應往往越小。

But given that, you might wonder why, since you get bitten all the time, you haven't become totally desensitized yet.

有鑑於此，你可能會想知道，因為你一直在被叮咬，為什麼還沒有變得完全脫敏。

Well, that's because even if you get bitten a lot, it's probably not enough.

嗯，那是因為即便你很常被叮，也可能是不夠頻繁。

If your goal is basically no reaction at all, that takes a lot of bites.

如果你的目標是基本上沒有任何反應，那需要大量叮咬。

Like, so many.

真的很大量。

In a prospective study from 1998,

在 1998 年一項前瞻性研究中，

researchers took a healthy 23-year-old man and an unlucky rabbit and exposed them to a species of mosquito neither had been bitten by before.

研究人員將一名健康的 23 歲男子和一隻不幸的兔子暴露於從未被叮咬的蚊子種類之間。

As expected, since it was their first encounter with that insect's unique blend of allergens, neither reacted much at first.

不出所料，因為這是他們初次接觸到這種昆蟲獨特的混合過敏原，兩者一開始都沒什麼反應。

Their bodies hadn't yet learned to recognize these proteins as foreign, so they weren't sensitized.

他們的身體還沒有學會將這些蛋白質列為異物，所以他們沒有被敏化。

But then, the pair regularly received between 100 and 150 mosquito bites⏤every two weeks for the person and weekly for the bunny.

但後來，兩者規律性地收到 100 至 150 個蚊子叮咬，人類每兩週一次、兔子每週一次。

Over the first several weeks, the bite reactions became larger and more uncomfortable.

在最初的數週裡，叮咬反應變得更大、更不舒服。

But, these brave mammals kept at it.

但這些勇敢的哺乳動物繼續堅持。

And after 20 weeks of this, the skin reactions noticeably declined.

而在持續這樣 20 週後，皮膚反應明顯下降。

By week 26 or so, both the man and the rabbit were basically reaction-free.

到了第 26 週左右，男子和兔子基本上都沒有反應了。

That sounds awesome, but if you do the math, it took between one and two thousand bites over half a year for the man to get to that point.

這聽起來很棒，但如果你計算一下，男人花了超過半年、被叮咬一至兩千次才達到這個地步。

That's just way more than anyone normally gets in a summer.

那比任何人在夏天普遍被叮要的次數都要來得多。

Of course, since the guy in the study was just one guy,

當然了，由於研究中的男子只是一個人，

there could be variation between people and how many bites are needed or how long the bite regimen has to go on for.

人與人之間可能存在差異，需要叮咬多少次、叮咬時間要多長有都會有所不同。

It's also unclear how long this desensitization lasts without maintenance doses of the allergens.

目前還不清楚在沒有維持過敏原劑量的情況下，這種脫敏作用能持續多久。

But if nothing else, we do know that long-term desensitization is possible because this one guy isn't the only person to become tolerant to bites.

但如果不出意外，我們確實知道，長期脫敏是可能的，因為這個人並不是唯一能容忍叮咬的人。

Biologists that raise large colonies of mosquitoes for research often feed them with their own blood,

為研究而飼養大型蚊子群的生物學家經常用自己的血來餵養牠們，

sometimes receiving hundreds of bites at a time, without reacting at all.

有時一次會被叮咬數百次，卻一點反應都沒有。

And studies suggest somewhere between 10 and 30 percent of people are just naturally tolerant to the bites from their local mosquito.

研究也顯示，大約有百分之 10 到 30 的人天生就是對當地蚊子的叮咬有耐受性。

So, you probably can make yourself essentially immune to these bloodsuckers⏤if you are willing to be bitten frequently for a long time.

所以說，你大概可以讓自己基本上對這些吸血蟲免疫，如果你願意長期、頻繁地被咬。

We are not recommending that you do that.

我們不建議你那麼做。

We are not doctors, and this is definitely the kind of thing that you should talk to an allergist about,

我們不是醫生，這絕對是你應該向過敏症醫生諮詢的事情，

especially if you're someone who has more severe reactions to mosquitoes.

尤其如果你是對蚊子有更嚴重反應的人。

Besides, it might not be too long before your allergist can help you get rid of those welts without thousands of bites.

此外，可能不用多久，你的過敏症醫生就能幫你擺脫這些傷痕，不需要成千上萬次的叮咬。

Specific immunotherapy for mosquito bites has been tested, and clinical trials have found it to be quite effective.

已經有對蚊子叮咬的特異性免疫療法的測試，臨床實驗也發現它是相當有效的。

But, also, there are some reasons you might not want to be completely unaware you're getting bitten.

但是，也有一些你可能不希望完全不知道自己被叮咬的原因。

Mosquitoes vector diseases, including a lot of really nasty ones, so, really, you want to avoid bites whenever possible.

蚊子是疾病的傳播媒介，包括很多非常討厭的疾病，所以說實話，你應該是想盡可能地避免被叮咬。

Having those bites show up and annoy you can serve as a warning that your anti-mosquito efforts aren't effective.

讓這些叮咬出現並煩擾你，可以作為一個警告，說明你的防蚊工作並不有效。

So, maybe some itchy bumps every summer is a small price to pay to keep you vigilant against the diseases mosquitoes transmit.

所以說，也許每年夏天幾個癢癢的包只是一個讓你對蚊子傳播疾病保持警惕的小代價。

And you can always stock up on citronella and deet instead.

而且你也可以隨時儲備香茅和除蟲劑來代替。

Thanks for watching this episode of SciShow.

感謝您收看本期 SciShow。

If all of this talk about mosquitoes has made you wonder why we have not just killed all of the mosquitoes to solve our problems,

如果這些關於蚊子的所有討論讓你想知道為什麼我們不直接將蚊子趕盡殺絕一勞永逸，

we've got an episode all about that that you can watch next.

我們有一集相關節目，你可以接著看。