(单词翻译:单击)
Mosquitoes are arguably the worst thing about the outdoors.
蚊子大概是户外最讨厌的东西了。
And if you're the kind of person who just seems to be eaten alive every time you step outside,
如果你每次出门都被咬的话
you might have wondered if there's some way you could become immune to their bites.
你或许想知道有没有什么方法可以让你免疫蚊子叮咬。
Well, I have some good news, you probably can, because mosquito bites are just a kind of allergic reaction.
好消息，或许可以有，因为蚊子叮咬只是过敏反应的一种。
But, like any allergy, the only way to become desensitized is with repeated exposure.
但和其他过敏一样，唯一脱敏的方法是不断被叮咬。
And I'm not talking about a few bites. I'm talking about thousands of them over months.
我说的不是几只蚊子几次叮咬，而是几个月内数千次的叮咬。
When a mosquito bites, she injects you with a chemical cocktail that helps numb the area and keeps your delicious blood flowing.
当被蚊子叮咬时，蚊子会给你注射一种化学成分帮助麻痹这个部分让你鲜美的血液不断涌出。
The chemicals themselves don't cause the redness, swelling, or itching, though,
这种化学物质本身不会引起红肿瘙痒，
your immune system's overreaction to them does.
但是人体免疫系统的反应会。
Which is why mosquito bites are considered a kind of mild allergic reaction.
因此蚊子叮咬被认为是一种温和的过敏反应。
Your immune system learns to recognize these proteins as foreign,
你的免疫系统学会将这些蛋白质视为入侵者，
and it primes specialized cells so that, the next time you're bitten, your body can launch a rapid immune attack.
并生成特殊细胞，这样下次被叮咬时，你的身体就会发动一种迅速的免疫攻击。
This is what's known as sensitization.
这被称为 敏化作用。
Specifically, mosquito proteins tend to activate the production of two kinds of immune weapons: IgE and IgG antibodies.
尤其是蚊子蛋白会刺激两种免疫武器的产生：IgE和IgG抗体。
When these antibodies bind to mosquito proteins, they ramp up the release of the molecule histamine,
当这两种抗体和蚊子蛋白质结合时，它们会增加分子组胺的释放，
and ultimately that causes those wonderful itchy bumps.
最终会引起痒痒的小包。
These antibodies can also cause much worse allergic symptoms, though, including full-on anaphylaxis.
这些抗体还会引起更糟糕的过敏反应，比如全面过敏性反应。
Exactly why severe reactions happen in some people and not others is something doctors are still trying to figure out.
所以一些人的反应会非常严重，而其他人却没有，医生也在试图找到原因。
But what we do know is that, for the most part,
但是我们可以明确的是，多数情况下
if you can become sensitized to something, you can also become desensitized to it.
如果你对某些东西过敏，你也可以脱敏。
The trick is to induce your allergic response so frequently that you end up convincing your body that reacting is a waste of energy.
诀窍在于，经常性地引导你的过敏反应，这样你就能说服你的身体—过敏反应不过是浪费精力。
That's the basic principle behind allergy shots, also called specific immunotherapy.
这是过敏疫苗注射的基本原理，也被称为特异性免疫治疗。
Doctors have developed standard protocols for allergens like pet dander and pollen.
医生开发了过敏源，比如宠物毛屑和花粉的标准试验方案。
But we know this same idea works with mosquito bites, too.
但是我们知道这种想法也同样适用于蚊子叮咬。
For example, the older you are and the longer you live in the same place,
例如，年纪也大，住在同一地方的时间越长，
the less your reaction to bites from local mosquito species tends to be.
你对本地蚊子叮咬的反应就可能越小。
But given that, you might wonder why, since you get bitten all the time, you haven't become totally desensitized yet.
但想到你也一直被叮咬，怎么还没有免疫力呢。
Well… that's because even if you get bitten a lot, it's probably not enough.
这是因为，即便你被叮咬很多次，可能还是不够。
If your goal is basically no reaction at all, that takes a lot of bites. Like, so many.
如果你的目标是几乎完全没有反应，那么需要被咬很多很多次。很多很多次。
In a prospective study from 1998, researchers took a healthy, 23-year old man and an unlucky rabbit
一项1998年的前瞻研究中，研究人员选择了一名23岁的健康男性和一只不幸的兔子
and exposed them to a species of mosquito neither had been bitten by before.
将他们暴露于一种蚊子中，他们之前都没被这种蚊子咬过。
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，自他们第一次和这种独特过敏源相遇起，两者起初都没较大的反应。
Their bodies hadn't yet learned to recognize those proteins as foreign, so they weren't sensitized.
他们的身体还没有学会将这些蛋白质识别成入侵者，所以他们没有过敏反应。
But then, the pair regularly received between 100 and 150 mosquito bites,
但是之后，两者定期被100到150只蚊子叮咬，
every two weeks for the person and weekly for the bunny.
人是每两周一次，兔子是每周一次。
Over the first several weeks, the bite reactions became larger and more uncomfortable.
开头的几个星期里，叮咬反应越来越大，越来越不舒服。
But, these brave mammals kept at it. And after 20 weeks of this, the skin reactions noticeably declined.
但是这些勇敢的哺乳动物继续坚持。进行了2周后，皮肤反应显著降低。
By week 26 or so, both the man and the rabbit were basically reaction-free.
到26周后，该名男性和这只兔子基本就没什么反应了。
That sounds awesome, but if you do the math,
听起来很棒，但是你算一下就知道
it took between one and two thousand bites over half a year for the man to get to that point.
要在半年多的是时间里被咬一到两千次才能到达这种效果。
That's just way more than anyone normally gets in a summer.
比在夏天被咬的次数多太多了。
Of course, since the guy in the study was just one guy,
当然，研究只对一个人展开，
there could be variation between people and how many bites are needed, or how long the bite regimen has to go on for.
人群之间还有很多变量，需要被多少只蚊子咬，要持续多久都不一样。
It's also unclear how long this desensitization lasts without maintenance doses of the allergens.
而在没有继续接触过敏源的情况下，这种免疫能维持多久还不清楚。
But if nothing else, we do know that long-term desensitization is possible
但最起码我们知道了长期脱敏是可能的，
because this one guy isn't the only person to become tolerant to bites.
因为这位男士并不是唯一一个能够忍受蚊子叮咬的人。
Biologists that raise large colonies of mosquitoes for research often feed them with their own blood,
生物学家培育了大量用于研究的蚊子，并经常用自己的血喂养它们，
sometimes receiving hundreds of bites at a time, without reacting at all.
有时一次被数百只蚊子咬，却完全没有什么反应。
And studies suggest somewhere between 10 and 30 percent of people
并且研究表明10%到30%的人
are just naturally tolerant to the bites from their local mosquitoes.
天生能够忍受本地蚊子的叮咬。
So you probably can make yourself essentially immune to these bloodsuckers, if you are willing to be bitten frequently for a long time.
所以你或许也可以对这些吸血鬼有免疫力，如果你愿意长时间经常性地被咬的话。
We are not recommending that you do that.
我们不建议大家这么做。
We are not doctors, and this is definitely the kind of thing that you should talk to an allergist about,
我们不是医生，你绝对应该和过敏症专科医师谈谈，
especially if you're someone who has more severe reactions to mosquitoes.
特别是如果你是那种对蚊子有严重过敏反应的人。
Besides, it might not be too long before your allergist can help you get rid of those welts without thousands of bites.
此外，在你的过敏症专科医帮你摆脱红肿前，要不了多久你就可以在不被数千只蚊子咬的情况下，有免疫力。
Specific immunotherapy for mosquito bites has been tested, and clinical trials have found it to be quite effective.
已经有一种针对蚊子叮咬的特殊免疫方法在接受测试，临床试验发现这种免疫方法相当有效。
But also, there are some reasons you might not want to be completely unaware you're getting bitten.
有几点原因会让你并不想完全察觉不到自己被咬了。
Mosquitoes vector diseases, including a lot of really nasty ones, so really, you want to avoid bites whenever possible.
蚊子携带疾病，包括很多糟糕的疾病，所以你想要避免被叮咬。
Having those bites show up and annoy you can serve as a warning that your anti-mosquito efforts aren't effective.
叮咬后的瘙痒可以被当成是一种警告—你的蚊子反抗努力没有效果。
So maybe some itchy bumps every summer is a small price to pay to keep you vigilant against the diseases mosquitoes transmit.
或许每年夏天痒痒的小包是让你警惕蚊子传播疾病的小代价。
And you can always stock up on citronella and deet instead. Thanks for watching this episode of SciShow!
你可以囤一点香茅油和避蚊胺。感谢收看本期《科学秀》！
If all this talk about mosquitoes has made you wonder why we have not just killed all of the mosquitoes to solve our problems,
如果本期视频让你想知道为什么不杀光世界上的蚊子解决我们的问题，
we've got an episode all about that that you can watch next.
我们有一期关于这个的视频，你可以去看看。
