Category Archives: Public Health/Coronavirus

Adoption of contact tracing app in France off to a very slow start

France was one of the first Western countries to build an app to track exposure to the coronavirus, but sluggish takeup rates could limit its usefulness in preventing a second wave.

Source: French Contact-Tracing App Struggles with Slow Adoption. It Isn’t Alone – WSJ

What many do not understand is that it requires a lot of people to have a smart phone and to install and use the app for a phone to detect potential coronavirus exposures.

To illustrate – in most modern countries about 80% of adults have a smart phone (plus or minus). When we adjust the figure for young kids who do not have a smart phone, about 2 in 3 people have a smart phone or 63%.

If half of all smart phone users install a contact tracing app, then we have about 32% have the app. In order to detect a contact, you need to be close to someone else with the same app. The probability of that occurring is .32 x .32 or 10%. Thus, what seems like wide spread adoption yields a potential of detecting just 10% of possible Covid-19 contacts.

And this probability does not take into account the problems with contact tracing apps:

  1. Incapable of detecting contacts across time (someone sits on a bus seat, coughs, gets up, leaves, and then you sit there)
  2. Difficulties with multi-path radio signals that result in false signal strength readings (this is common)
  3. Incapable of detecting when there is a barrier between contacts. For example, you are on a bus stopped at a bus stop while the driver takes a break. Someone with Covid-19 standing outside the bus results in alerting your phone that you just had a contact. Except you really did not due to the physical barrier.

Japan pulls its coronavirus tracking smartphone app due to software design errors

The Japanese government has pledged to fix within a week bugs that have caused its coronavirus contact-tracing smartphone app to be shut down, the health minister said Tuesday.

The free app, which was launched Friday and downloaded around 3.71 million times as of Tuesday morning, erroneously accepts ID numbers not issued by the Health, Labor and Welfare Ministry, Katsunobu Kato, the minister responsible for the system, said at a press conference.

Source: Bugs force Japan gov’t to temporarily shut down virus contact-tracing app

UK smart phones display feature update for contract tracing – but its confusing as its not actual contact tracing

Update: The UK government terminated its contact tracing app trial, on going since the beginning of May and will now develop a new contact tracing app based on the Google/Apple Bluetooth tech.

More confusion and incoherent messaging in the public health domain:

A Covid-19 tracing software tool has appeared in the settings of both Android phones and iPhones as part of an update of their operating systems.

….

In the UK there is currently no available contact-tracing app.

The update has caused some confusion, with people querying the new addition to their handsets on social media.

Source: Coronavirus: New Covid-19 tracing tool appears on smartphones – BBC News

Sounds like the UK is starting over. Their original app used a central cloud-database and now they will develop an app based on the Bluetooth, no-cloud storage model.

Australia’s Bluetooth-based contact tracing app deemed largely irrelevant

Says they’ve identified a total of … one person:

The PM told Australians in April the contact tracing app was key to getting back to normal but just one person has been identified using its data

Source: How did the Covidsafe app go from being vital to almost irrelevant? | World news | The Guardian

Remember, Singapore pulled their Bluetooth app. Norway used both Bluetooth and GPS and pulled their app for EU privacy problems. The UK’s been testing their Bluetooth app on the Isle of Wight – was supposed to have gone nationwide more than a month ago but since then, things have gone quiet.

7 in 10 Americans won’t use contact-tracing apps

No surprise: More than 7 in 10 Americans won’t use contact-tracing apps, data shows | Ars Technica

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.

Norwegian Institute of Public Health cancels their smart phone tracing app due to privacy issues

One of the first national coronavirus contacts tracing apps to be launched in Europe is being suspended in Norway after the country’s data protection authority raised concerns that the software, called ‘Smittestopp’, poses a disproportionate threat to user privacy — including by continuously uploading people’s location.

Source: Norway pulls its coronavirus contacts tracing app after privacy watchdog’s warning | TechCrunch

It had been downloaded by 16% of the population over the age of 16. That means it could detect .16 x .16 or about 2% of potential contacts. It appears their app was based on location data, centrally stored, plus used the ineffective Bluetooth RSSI method of detecting potential contacts.

It appears that public health enthusiasts had used the “laws don’t matter in a pandemic excuse” to justify violation of EU privacy laws.

Smartphone tracking apps lose favor: “What happened to all the coronavirus tracking apps? – CNN”

Last week, Singapore pulled the plug on its own Bluetooth-based smart phone contact tracing app:

Covid-19 tracking apps were hailed as a way to help countries out of lockdown. Instead many have been delayed, and those that are out are not being downloaded at the rates experts say are needed to have a major effect.

Source: What happened to all the coronavirus tracking apps? – CNN

The apps cannot work unless nearly everyone in the country has a smart phone and installs the app. Furthermore, they are incapable of tracking contacts across time (scenario: sit on bus, cough, get up, leave, next person sits in seat, contacts viral load – apps miss this completely).

Lots more here on why Bluetooth-based, smart phone tracking apps are very unlikely to work well.

The U.K. is testing their own Bluetooth-based app on the Isle of Wight and news reports suggest the test is not going well. The NHS is being secretive about what they are learning. The app was originally to have been rolled out nationwide about 3 weeks ago… but for now, there are no updates on the test. Another problem is the U.K.’s system is a privacy nightmare.