Quitting smoking is contagious, says study - The Times 22nd May 2008

Smoking may be addictive but quitting is contagious, according to a provocative study of why people give up the weed. The act of quitting passes through a social network like an outbreak of flu. Husbands are likely to pass it on to their wives, or vice versa, workers to colleagues, brothers to sisters, friends to friends. But neighbours seldom catch it over the garden fence. Mere proximity is not enough. You have to know somebody who is quitting, and the better you know them, the more likely you are to give up yourself.

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