A new study suggests that people, regardless of travel habits, follow the same general patterns of motion, spending the bulk of their time in a few favorite spots. The conclusions, obtained by tracking thousands of mobile phone users, could help researchers devise more accurate models of disease outbreaks.
Human travel routines affect how a virus will spread during an epidemic. But monitoring large numbers of people isn't easy. A 2006 study using hundreds of thousands of dollar bills as surrogates found that a typical bill circulated within a small area but could also travel long distances when its owner went on a trip or vacation (ScienceNOW, 25 January 2006). It wasn't clear whether this pattern reflected the movements of individuals, however, because a dollar bill can easily change hands.
So physicist Albert-László Barabási and his team turned to the most ubiquitous of human accessories: the cell phone. They monitored 100,000 users for 6 months and recorded the location of the cell phone tower that transmitted each call or text message. Read about their findings @ http://sciencenow.sciencemag.org/cgi/content/full/2008/604/2
