With 30% agreeing to install such apps today, that means just 9% of potential contacts could be detected.
The apps have a host of real problems:
- insufficient users to be useful. At 50% adoption, we can detect only 25% of potential contacts.
- unreliable signal strength-based distance determination, which fails in radio signal multi-path situations
- unable to detect when a barrier separates contacts. You sit outside at Starbucks and someone sits inside at a table. The inside person later tests positive for Covid-19. You receive a message. But they give you no indication where or when the contact occurred – so you have to go into quarantine for 14-days, delivering no benefit to anyone. This error can occur in buildings (through walls) or even between cars stopped at traffic signals or heavy traffic.
- unable to detect “across time” contacts. Person sits on bus, coughs, gets up, exits bus, new passenger sits in coughed on seat. These apps cannot detect this. Person sits at Starbucks tables, coughs, gets up and leaves, next person sits at contaminated table. None of these parties will be in Bluetooth contact and the apps will miss these contacts.
Bluetooth-based apps are not going to be effective. Singapore pulled the plug on their app due to insufficient users. The UK has been testing a Bluetooth app that was to have rolled out nationwide in mid-May. It’s still in testing and public information about the app has gone silent; it has not been rolled out yet. Norway has an app that uses both Bluetooth and GPS data, and used a central cloud database. This app was just ruled as violating privacy laws and has been pulled. Public health enthusiasts thought it was okay to violate privacy laws because laws do not matter to public health enthusiasts.
- I do not plan to install a tracing app on my phone.
- I do plan to be vaccinated as soon as vaccines are available.
- I was sick with Covid-19-like symptoms during almost all of March. Antigen tests were not available to normal people, only those who were already hospitalized with pneumonia and to the elite (like the Governor and her husband). My doctor suggested getting an anti-body test (end of May) but I declined as the accuracy is not sufficient (when the real world incidence is very low, the number of false positives will exceed true positives), and knowing if I was sick is not, at this time, actionable information.