Contagious as the Flu

[bluffmanxx]

In a good mood? Your neighbor, her friends and even her friends' friends should thank you – you're likely infecting them with your cheer. Happiness spreads through social networks about as easily as the flu, according to a new study.

Happiness: Contagious as the Flu

don't worry too much though if you are in a bad mood....

Sadness, thankfully, is not nearly as infectious. An attack of the blues creates a much smaller ripple than a case of giddiness, said head researcher James Fowler of the University of California, San Diego.