German Health Minister Karl Lauterbach told reporters Friday he expects a “massive” fifth wave of the COVID-19 pandemic driven by the omicron variant of the coronavirus that causes the disease. Lauterbach made the comments during a news briefing following a tour of a vaccination center in Germany’s northern lower Saxony state. During a press conference, Lauterbach, a former epidemiology professor, said he had been in close consultation with colleagues in Britain who say the omicron outbreak “exceeds everything we have seen in the pandemic so far.” The health minister said Germany must prepare for “a challenge that we have not yet had in this form.” He also said reports that the omicron variant leads to milder infection would not make any difference, as its ability to spread quickly would overwhelm any advantage that might be gained by more moderate symptoms. Lauterbach said he does not believe an omicron wave of cases can be prevented and that “it will be a massive challenge for our hospitals, for our intensive care units, but also for society as a whole.” The health minister said booster shots are the only reliable way of preventing a serious infection from the omicron variant. On Thursday, Lauterbach said accelerating vaccinations and booster shots is central to his COVID-19 strategy and that he was reaching out to other nations to obtain more vaccine doses. Germany has reimposed health restrictions following high case numbers, barring unvaccinated people from restaurants and non-essential commerce. Germany’s Robert Koch Institute (RKI) for Infectious Diseases on Friday reported 50,968 new cases over the previous 24 hours. While the number of overall active cases declined, RKI said it has not dropped quickly enough, as intensive care units remain under stress. Some information for this report was provided by The Associated Press, Reuters, and Agence France-Presse.