Itching and Scratching

Itching and Scratching, written by Susan Lennox. Focus question. Why do our bodies itch? And how can we get rid of itchiness?

《痒乎乎抓不停》，作者：苏珊·伦诺克斯。 思考问题： 为什么我们的身体会发痒呢？ 我们又该怎么止住痒意呢？

Tickle, touch, scratch. It starts with a tickle. You brush your hand against your skin, but the tickle continues. You can't help but scratch. Ah, relief, but it lasts just a moment. Then the feeling returns, even stronger. Before long, you're scratching away again. We've all had that experience. There are dozens of reasons for itching. And there's a good explanation for why scratching seems to relieve an itch.

痒痒，摸摸，抓抓。 一开始只是一丝痒。 你伸手蹭了蹭皮肤，可痒意还没消失。 你忍不住抓了起来。 啊，舒服多了，可这轻松只维持了一小会儿。 接着痒意又回来了，比之前更厉害了。 没过多久，你又开始抓个不停了。 我们都有过这样的经历。 发痒的原因有许许多多种。 而为什么抓挠能缓解痒意，这里头大有说法。

more than skin deep. When you think of itching, you usually think of skin. It's true that itching happens mostly on your skin. After all, skin covers your whole body. Skin is also the only thing that stands between the inside of your body and the outside world. All sorts of things touch your skin. Skin has nerve cells that react when something touches it. Some of those things are harmless. Some, however, are harmful or even dangerous. An itch is your body's way of warning that these things can hurt you. For example, many people are allergic to poison ivy. This plant has irritating oils that rub off on skin. The oils make skin blister and ooze. Open blisters can get infected. The oils can also affect other parts of the body, like the nose and lungs. Contact with poison ivy can cause a bad infection to develop.

痒的学问可不只在皮肤表面。 想到发痒，你通常最先联想到皮肤。 没错，发痒大多都发生在皮肤上。 毕竟皮肤包裹着我们整个身体。 皮肤也是隔开身体内部和外界的唯一屏障。 各种各样的东西都会接触到皮肤。 皮肤上有神经细胞，碰到东西就会做出反应。 有些接触是完全无害的。 但有些是有害的，甚至十分危险。 发痒就是身体给你的警告：这些东西会伤害你。 举个例子，很多人都对毒常春藤过敏。 这种植物带有刺激性油脂，会沾到皮肤上。 这些油脂会让皮肤起水泡、流渗出液。 破掉的水泡很容易发生感染。 这些油脂还会影响鼻子、肺这类其他身体器官。 接触毒常春藤可能会引发严重的感染。

Your body uses itching to keep infections from happening. Itching is a signal from your immune system, your body's internal system that helps protect you from sickness. When you touch poison ivy, your immune system triggers an itch. This informs you that your skin has touched something harmful. In this case, the itch teaches you to stay away from poison ivy.

身体靠发痒来预防感染发生。 发痒是免疫系统发出的信号，免疫系统是帮你抵御疾病的身体内部系统。 当你碰到毒常春藤，免疫系统就会触发痒意。 这就是在告诉你，皮肤碰到有害的东西了。 这么说来，痒就是在教你离毒常春藤远一点。

Causes of itching. It's not just your skin that itches. Your eyes can feel itchy too. And so can your nose and throat. Scratching is a reflex action to itching. Something you do automatically or without thinking. However, you can't reach down your throat to scratch it, so you cough. You can't scratch inside your nose, so you sneeze. Scratching your eyes can cause damage, so you rub them instead. All those actions have the same goal, to remove whatever is causing the itch. Perhaps you ate something spicy. Maybe you breathed dust or got smoke in your eyes. A good cough, sneeze, or rub could get rid of the problem.

发痒的原因 会发痒的可不只有皮肤哦。 眼睛也会觉得痒痒的。 鼻子和喉咙也同样会发痒。 抓挠是发痒触发的反射动作。 也就是你不假思索，不自觉就会做的动作。 但你没办法伸手挠喉咙，所以你会咳嗽。 你也没法挠鼻子里面，所以你会打喷嚏。 直接挠眼睛会受伤，所以你会改成揉眼睛。 这些动作的目标都一样：弄走引发发痒的东西。 也许你吃了辛辣的食物。 也许你吸进了灰尘，或是烟飘进了眼睛。 好好咳一声、打个喷嚏或是揉一揉，就能解决问题啦。

Sometimes, though, you can't get rid of the cause of your itch easily. Sometimes, the cause comes from a germ inside your body. The itch you feel may be part of a sickness caused by the germ. Chickenpox is a sickness caused by a virus. The virus makes the skin break out in very itchy blisters. Today, many children get a vaccine to prevent them from getting chickenpox. Luckily, for those who do get sick, chickenpox is a temporary condition. After a while, the sickness passes.

不过有时候，你没法轻易去掉发痒的源头。 有时候，发痒的源头来自身体内部的病菌。 你感觉到的痒，可能就是病菌引发的疾病的症状之一。 水痘就是病毒引发的疾病。 这种病毒会让皮肤长出奇痒难忍的水泡。 现在很多小朋友都会接种疫苗，预防水痘。 幸运的是，就算出水痘，也只是暂时性的。 过一段时间，病就会痊愈。