What is the most contagious prank?

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This is one video which will make you both laugh and yawn at the same time! Sounds too ironic to be true, but this YouTube prankster’s video is generating, quite literally, several open-mouthed expressions of boredom and hits. Roman Atwood travels across the globe, infecting passersby with his yawn.

According to The Daily Mail, he visits top tourist destinations, such as Paris, Egypt and Rome, and walks by unsuspecting victims, stretches and yawns in front of them. They immediately yawn back as if in response to his overture, and these reactions are caught on camera and compiled into a really funny video.
But not all take his yawning lightly. In one instance, Roman is accused by two men who accuse him of unnecessarily walking up and down, yawning, and spreading his germs. One of them even suggests that Roman should go home and get some rest.
At the end of the clip, a man is seen yawning while his dog is close to him. The pet too is infected and ends up yawning.
Clearly, it’s not just laughter that is contagious! The video has over 2,533,951 hits and is still, let’s say, catching on! The prank could have its uses — to prod a speaker at a seminar not heeding the stopwatch to make his ending remarks maybe?