An App That Lets You Track Down Who Got You Sick | changing healthcare |

The Facebook app uses different clues to determine which friends are sick by checking status updates for words, such as "flu" "sneezing" and "coughing," and looking at places those people might have checked in. Even the times your friends have posted are considered relevant. For example, several late night posts may indicate a person hasn't been sleeping enough and, thus, would be more susceptible to catching -- and passing along -- the bug.