Could a smartwatch identify an infection before you start spreading it?

This shows a smartwatchA medical wrist device detected disrupted sleep patterns 24 hours before participants started shedding the flu virus. While the initial study was focused on influenza, researchers speculate the device could be sufficient at spotting the beginning of other infections, including COVID-19. While it should not be considered a full diagnostic device, the wristband data will be useful to guide when people should self isolate as a precaution.