App against virus: How corona apps can dampen the fourth wave of infections
Smartphone apps to combat the corona pandemic hardly played a role in Germany last summer. The federal government’s official Corona warning app was already installed on around 25 million devices at the time. But in the first week of July, the number of red warning messages that signal high-risk contact with an infected person did not even reach the threshold of 100. During these weeks there were hardly any infections that could be detected. But now the situation is serious again.
The dramatic development can also be seen in the app statistics. In the Corona warning app, the number of red warnings soared to over 70,000 cases every day in the past week. The Luca check-in app also saw a steep increase in warnings. Last week, after a detailed risk assessment, the health authorities in Germany issued over 40,000 individual warning messages to Luca guests. Critics of the Luca system, however, complain that a number of health authorities do not work actively with Luca.
The official Corona Warning App (CWA), for which 36.3 million downloads have now been recorded, uses Bluetooth signals to record which smartphones have come close to each other and then notifies users of risky encounters. The Luca app, on the other hand, is intended to help restaurant owners and event organizers to do the legally required recording of visitor contacts without a mess of paper. It doesn’t track users all day. After a check-in, it can enable targeted warning messages based on the pattern “You have been sitting at a table in location X for about one and a half hours not far from multiple infections”.
While data protection officers are repeatedly bothered by the central data storage of the Luca system, a decentralized data protection concept was implemented at the CWA, which is also considered exemplary internationally. With all the praise for data protection: The effectiveness of the CWA, on the other hand, is questioned again and again, also because the app has shown significantly fewer “green” – i.e. less dangerous – risk encounters since the algorithm was changed a good year ago. Bavaria’s Prime Minister Markus Söder (CSU) presented the Corona warning app as a flop. “Unfortunately, the app is so far a toothless tiger. It has hardly any warning effect,” said the politician in an interview in October 2020.
The thesis of the “total failure” of the CWA is refuted over a year later by figures from the Robert Koch Institute. It was not only Prime Minister Söder who had the impression that the app was virtually dead because of the rare warning messages. In the meantime, around 710,000 people have warned other people about a dangerous risk encounter via the app. It is estimated that over 300,000 cases of infection chains have been broken as a result.
The number of relevant warnings could, however, be much higher if all users of the app who tested positive also entrusted this bad news to the app. Initially, however, not even 40 percent of those affected dared to trigger this chain of alarms. Most recently, this value has improved to around 60 percent.
When evaluating the numbers, however, it must also be taken into account that some of the results that were not shared were tests that CWA users registered in their app for other people, such as their children or other relatives, explains an RKI- Speaker. In these cases, there is a good reason not to share the negative test in the app, because otherwise the wrong contact person would have been warned in some cases.
The digital vaccination certificate has triggered a boost in the use of Corona apps. It can be saved in the special CovPass app, which otherwise has no other functions, or in the CWA and Luca. But since the yellow vaccination booklet is not forgery-proof, you cannot completely rely on the fact that the digital images of the vaccination certificate were rightly issued. In addition, there is hardly any verification that the QR code shown belongs to the person who is holding the smartphone. But that has less to do with the apps themselves than with how they are used.
Elsewhere, however, the apps themselves are confusing for some users: Both the Corona warning app and the Luca app offer a “check-in”, but this has different effects. At the RKI’s CWA, a check-in only calculates the distance measurement in the room according to a different formula. Visitors who have already checked out are taken into account, for example, who left the event a few minutes ago, but whose aerosols could still be floating in the air. In contrast to the Luca app, the CWA does not transmit any contact details. With Luca, on the other hand, the place, the time of stay and the contacts of those involved are recorded.
In 14 out of 16 federal states, the respective state infection ordinances still stipulate that innkeepers and event organizers must record the contacts either with Luca, a comparable app or on paper. Only Saxony and, since mid-October, Baden-Württemberg also allow check-in with the Corona warning app without entering contact information. That could set an example now.
The Bundestag passed a reform of the Infection Protection Act on Thursday, in which the Corona warning app is explicitly mentioned as a possibility for contact tracking. The law states that, as an alternative to the collection of contact details, “it can also be ordered that the tracking and interruption of chains of infection” take place primarily through the provision of the QR code registration for the Corona warning app.
Federal states with intensive use of Luca, such as Hamburg, will probably rely on the parallel use of CWA and Luca in the future. In other countries such as Brandenburg, however, there are discussions about not extending the existing Luca contract at the end of the year. (dpa / rs)