Since the beginning of the COVID-19 pandemic, dozens of countries have deployed digital apps that attempt to identify people exposed to the SARS-CoV-2 coronavirus and stop onward transmission. But evidence that these ‘contact-tracing’ apps work has been hard to come by, because most collect limited data to protect users’ privacy. Now, studies from a handful of nations show mounting evidence that apps can help prevent infections and are a valuable public-health tool.
These data are really appreciated, especially when it comes to decision-making — should we adopt the app or not? says epidemiologist Viktor von Wyl at the University of Zurich, who has been evaluating Switzerland’s SwissCovid app.
Researchers say that contact-tracing apps won’t by themselves bring the pandemic under control. But the results show they are useful, providing that they have adequate political backing and are properly integrated into public-health systems.