My thoughts at the time: Close contact detection and alerts at the mobile OS level We need to get better and faster at stopping the spread of infectious disea

My thoughts at the time: Close contact detection and alerts at the mobile OS level We need to get better and faster at stopping the spread of infectious diseases. Covid is already catastrophic. Next time R could be 5, and mortality could be 5, 10 or 20%. I believe we can use mobile technology to track close contact between individuals, and alert at-risk individuals to potential infections. I believe this could drastically reduce R and the impact of infections diseases could be substantially mitigated. Simulations should be able to determine the effective reduction of R. Apple and Google should work together to implement a worldwide close contact logging framework. It will use bluetooth to track close contact encounters. The architecture will be anonymised and encrypted to make it somewhat privacy centric. Obviously privacy zealots will make noises, but to save millions of lives and economic disaster the general population could be convinced it's acceptable. iOS and Android should have an always-on bluetooth scanner that logs the bluetooth ID of nearby devices. If a device stays nearby for a certain amount of time, a close contact is triggered. The severity of the close contact is determined by the amount of time the devices were close together for, and other bluetooth data. This is anonymised, encrypted and logged. When an individual is diagnosed with an infectious disease, they activate a feature in their phone which displays a QR code. The health professional has an app that scans the QR code. The health professional will enter details about the disease, and how far into the past the person was estimated to be contagious. Alternatively if the individual hasn't been tested or is unable to reach a health professional, they can answer a set of questions about their symptoms that will determine how likely they are to be infected. Obviously this method of self diagnosis is less reliable so the framework will take this into account when deciding who to deliver alerts to. The system alerts people that have had close contact with the infected individual, giving advice about local testing centers or self quarantine. The system will be tuned to only notify the more severe close contacts as needed. Data about available local testing capacity could be used to further refine this tuning. Problems: * Privacy: how to make the data private / anonymous. Communication: how to convince the public that their data is private / anonymous? * Power: Bluetooth on all the time - battery drain? * Health professionals: how to make sure only health professionals can use the alert app, but also deploy worldwide without delays. * Deployment: how to get this system onto all Android phones with such a fragmented ecosystem. * Detection: how to most effectively determine infection risk from available bluetooth data. * Tuning: too many alerts for low risk encounters and people will ignore them - tuning is needed.