4 ms·

Exactly what I was thinking - I don't see how this approach will work in practice with the time it takes to find and positively identify a Covid-19 case, as the

• g_p 6y ago
  If the clinical results of the 20-minute lab-free test the UK is trialling [1] are positive, I could see this working. But that's a risk. To my mind, this is a simple matter of reducing the time the "next generation" of infected people are in the community before being notified. If that can be below 3 days, I think the disease can be managed based on the law of averages. If not, it seems it will continue to spread. That's why, absent a national "Amazon Prime Now" style <= 2 hour delivery window for tests (and some way to verify the results of these tests for input to a decentralised app), I don't see this working. The app will only really be needed/helpful in cases where you don't know people you are in close or prolonged proximity to, i.e. shops and public transport. In these cases, it makes sense to notify as early as possible, even at the risk of some false positives for those not actually infected, but who were close. The question is how many FPs there will be, but this also happens with human-based contact tracing too. [1] https://www.theguardian.com/world/2020/may/21/uk-coronavirus-test-with-20-minute-wait-being-trialled https://www.theguardian.com/world/2020/may/21/uk-coronavirus...