Classroom rosters combined with human-networking theory may give a clearer picture of just how infectious diseases such as influenza can spread through a closed group of people, and even through populations at large. Using high-school schedule data for a community of students, teachers, and staff, Penn State University scientists have developed a low-cost but effective method to determine how to focus disease-control strategies based on which individuals are most likely to spread the infection.
The team members gathered data from classroom rosters and formulated a "collocation rank" -- the cumulative time each individual is potentially exposed to other individuals -- for all students, teachers, and staff members at a high school. These collocation ranks were calculated from information about each class taught at the school -- which teacher taught the class, the room in which the class was taught, the period of the class, and the number of students who were enrolled in the class.
The results show that classroom schedules can paint a fairly accurate picture of the frequency of person-to-person interactions, of which individuals have the most person-to-person contacts, and of the likelihood that disease will spread in the event of an outbreak. More information is online at