BERLIN (Reuters) – Germany’s smartphone app to trace coronavirus infections is ready to be launched this week, Health Minister Jens Spahn said on Sunday.

After delays to ensure the bluetooth technology would work at the correct distance, the government says the app will be a vital tool to help avoid a second wave of infections.

“It’s coming this week,” Spahn told ARD television, but he declined to confirm German media reports that the app would be launched on Tuesday.

The app uses bluetooth short-range radio to detect and contact people at risk of infection by coronavirus and does not rely on a centralised database. Deutsche Telekom and software company SAP are involved.

Italy launched a similar app last week.

Spahn also urged people wishing to go on holiday after European border controls are eased on Monday to be careful and ask themselves whether their trip was necessary.

On Monday, Germany lifts its blanket travel warning for European Union nations and Britain, and will replace it with specific travel advice for individual countries and regions.

“We need the right balance,” Spahn said, adding that recent outbreaks in Germany after mass gatherings and church services had caused a rapid spread of the virus.

Thanks to large-scale testing, a robust health system and lockdown measures introduced in mid-March, Germany has kept the number of deaths from COVID-19 relatively low compared to other countries despite a large number of cases.