According to figures released by Health Ministry, the number of hospitalized jumped to 1,695 on Monday, up from 1,537 the previous day.
It had been declining since Dec 6 when the previous wave, caused by the delta variant, peaked at 7,135 people needing hospital treatment.
The omicron variant spreads even more easily than other coronavirus strains. It also more easily infects those who have been vaccinated or had previously been infected by prior versions of the virus. However, early studies show omicron is less likely to cause severe illness, especially for those who have had two vaccinations and a booster.
Anticipating the surge, the Czech government cut isolation restrictions for those testing positive for COVID-19 from 14 days to five, and also similarly shortened quarantine times for close contacts of infected people.
It also has decided to allow workers in health care and nursing homes who have no symptoms of COVID-19 to stay on the job even if they test positive.
The Czech Republic, a European Union nation of 10.7 million people, has seen over 37,000 COVID-19 patients die in the pandemic.