Corona-Warnapp proves effective according to initial studies
Quickly alerting contacts and relieving the burden of manual contact tracing: these are the advantages of the Swiss Covid app. It makes an important contribution to pandemic control, as Viktor von Wyl, UZH Professor of Digital and Mobile Health, writes in an article. But the digital tool also harbors some pitfalls.
Swiss researchers analyzed the effectiveness of the Swiss Covid app, which is currently used by over 1.8 million people, in several studies. One of the studies was based on people identified as contacts of infected individuals through contact tracing by the Canton of Zurich. It showed that contacts at risk of infection outside their own household quarantined themselves about a day earlier when they received an alert from the app - compared to people without an alert.
Even though one day may not seem like much, this can have an influence on the course of the pandemic, according to various models, says von Wyl. In contrast, no difference can be observed among contacts from the same household due to short communication paths.
30 possible infection chains interrupted
In a second study, the researchers showed that in the month of September, about 170 contacts warned by the app in the canton of Zurich received a quarantine recommendation. This corresponds to about five percent of all persons who were given a mandatory quarantine by classical contact tracing.
In addition, 30 contacts tested positive for coronavirus following an app warning. Accordingly, 30 possible chains of infection were broken within one month.
Bottleneck: Covid codes
However, it turned out that one in three people infected with the coronavirus did not trigger a warning via app. The reason: there were repeated delays in issuing the so-called Covid codes, according to von Wyl. Since all doctors are now allowed to issue such codes, thus relieving the cantonal health offices, this problem could be reduced. Rapid antigen tests also help to speed up the warning cascade.
In order for the warning app to be even more effective, it is important that even more people use it, von Wyl concluded. He hopes that these initial, encouraging studies will help to ensure that previously hesitant sections of the population now give the app a chance. (SDA)
