Patent ID: 8645538

Claim:
A method of tracking a history of person-to-person interaction through the use of personal handheld computing and communication devices for monitoring outbreak of a contagious disease, the method comprising: (a) establishing an ad hoc communication network by a plurality of handheld computing and communication devices when said handheld devices are within a predetermined distance in a location, each of said personal handheld devices is stored with an identity associated with each of users; (b) broadcasting each of the identities by each of said handheld devices through said ad hoc communication network; (c) receiving and recording in a log file by each of said handheld devices all other identities of other handheld devices; (d) receiving an authorized signal by at least one of said handheld devices from a central station through a communication network; and (e) transmitting the log file in said one of said plurality of handheld devices to the central station through the communication network, wherein said predetermined distance is adjustable by a program stored in said handheld devices, wherein said predetermined distance is determined by nature of the contagious disease.