https://www.sciencedaily.com/releases/2021/09/210928102237.htm

In the spring of 2020, the COVID-19 pandemic was spreading rapidly across Europe. After initial hesitation, in mid-March the German government and the Conference of Federal State Prime Ministers (Ministerpräsidentenkonferenz) decided in quick succession on a series of measures to restrict social contacts, including the closing of schools, childcare facilities, and shops. Even private meetings of people from different households were limited. German policy-makers thus implemented rapid and far-reaching contact restrictions. In the early stages of the first wave of the virus, masks were not yet mandatory. Neither vaccinations nor rapid tests were available. Within a few weeks, COVID-19 infections in the country declined sharply, causing contact restrictions to be gradually relaxed again beginning on 20 April 2020.

Despite the rapid decline in infections in Germany, the effectiveness of the contact restrictions has been disputed repeatedly, both by the public and by experts. In particular, it was argued that even without the enacted measures, the spread of the virus would have been curbed by automatic changes in people's behaviour.