非典十年后，港人摘下口罩

    假设你在香港挤公交车，现在是流感季节，而你不想生病。“看看周围，”司徒博士建议，“如果有人咳嗽，离他远点就行了！哈哈！至少保持一米的距离！如果你看到有人表现出流感的症状，那就闪人！”

    如果有人正好对着你的脸打了个喷嚏，那该怎么办呢？“遇到这种情况，你得记住一点，”司徒博士说，“没有什么细菌是能在接触到你的一刹那就让你患病的。只有电视上的东西才会那么夸张，比如恐怖科幻片《幽浮魔点》（The Blob），上面描述的那种细菌能让人瞬间融化。医学当中有个词叫‘潜伏期’；病毒需要潜入你的身体，它需要以正确的方式附着在细胞上，然后自我复制。要是有人对着我的脸咳嗽，我怎么办？没事！洗脸，洗脸，再洗脸！别的什么都不用做！”

    至于戴口罩防病，“我不推荐这种方法。”司徒博士说。首先得选对口罩，要双层的，里层能透气，外层能防水。（“告诉你吧，你去公交车里看就知道了，好多人都戴错口罩了。”）戴口罩时要把嘴巴、鼻子都遮住。（“要戴眼镜。”）不能整天都戴同一个口罩。（“你得记住，戴上口罩在外面转了一圈之后，口罩就变脏了。要是不会变脏，那我们还戴它做什么？”) 脱下来的时候要非常、非常的小心。（“要是你戴着口罩出去，路上有患病的人，那么这个口罩就会沾上病菌。你一碰到它，病菌就跑到手上去了。”）

    司徒博士承认，关于最后要提的这个事实，虽然也不是没有争议，但他的立场是坚定的：“我们现在基本上认为，如果一个人没有症状，就可以视为尚未感染。”也就是说只要你没打喷嚏，就算感觉身体不适，也不会威胁到其他人。

    好吧，假如一个人身体真的很不舒服，又咳嗽、又流鼻涕、又打喷嚏的，那么是不是应该至少戴个口罩呢？别的不说，至少在拥挤的公交车里也该为其他乘客想想吧？“如果你病了，”司徒博士说着，咧开嘴笑了，“那就老老实实在家里呆着。”非常简单。

    译者：Nasca

    Say you're on a crowded Hong Kong bus, it's flu season, and you don't want to get sick. "Look around," Dr. Seto advises. "If someone is coughing, just stay away from that guy! Hah-hah! At least one meter! If you see someone with symptoms, move away!"

    And if by chance someone sneezes in your face? "This you must believe me," Dr. Seto says. "There is no bacteria on earth that clobbers you the moment it touches you. That's TV. The Blob, the guy melted right away. There is something in medicine called the incubation period. The virus needs to get into you; it needs to attach the right way, multiply. Someone coughs in my face, what do I do? No problem! Wash, wash, wash, wash! That's all you need to do!"

    As for wearing a mask to protect yourself, "I would not recommend it," Dr. Seto says. You need the right kind of mask, first of all, one with two layers. Absorbent side in, waterproof side out. ("I tell you, if you go to the bus you see all these idiots wearing it the wrong way.") You need to cover your mouth and your nose. ("And wear spectacles.") You don't want to wear the same mask all day. ("It's good practice to say once you put it on, consider it dirty. If it's not dirty, why are you wearing it?") And be very, very careful when you take it off. ("If you're infectious and I'm wearing a mask, now the mask is infectious. I touch it and it's on my hands.")

    Last fact. Well, not an undisputed fact. There is still some debate about this, Dr. Seto allows, but his own view is firm: "Generally we now believe that if you have no symptoms, you can be considered not infectious." Meaning as long as you're not sneezing, even if you don't feel quite right, you're not a threat to others.

    Okay but let's say you really are sick. Runny, slobbery, sneezy sick. Can we at least agree that then you should wear a mask? If for no other reason than to protect your fellow passengers on that crowded bus? "If you are sick," says Dr. Seto, grinning, "stay home." Very simple.