Human evolution and persistent diseases have existed side-by-side. A recent concern is the re-emergence of tuberculosis, one of the oldest and most challenging diseases known to man. Effective diagnosis can save lives and prevent its spread. This talk will cover how our immune system discriminates between itself and foreign entities and how a new laboratory and nature inspired strategy can detect tuberculosis equally well in human and animal populations. The approach is being extended to other applications such as the identification of strep throat and respiratory infections.