Are you sick or just paranoid?

One of the most unusual things I've observed in Japan is the number of people who wear masks. Not Halloween masks or Basel Fasnacht masks, but what I would describe as surgical masks. All sorts of people wear them-- kids in school uniforms; men in business suits; young, beautiful, fashion-setting women, old ladies in kimonos, etc. My very unscientific polling research tells me that about 1 in every 20 people in Tokyo is wearing one. I wondered if this was a hold-over from the days of SARS because it reminded me of all those news stories we used to see in the US about SARS in Asia. Apparently this "trend" long preceeded SARS. Our Japanese friends told us there are two categories of people who wear masks: those who are sick and don't want to infect others, and those who have really bad allergies and are already concerned about the upcoming pollen season. Surprisingly, they didn't say "paranoid people". That would be my addition to their list.