All Czech employees will have to undergo antigen tests twice a week as the Omicron strain of Covid-19 is expected to spread, the health minister said Wednesday.

The measure taking effect on January 17 affects all employees going to regular workplaces, and includes vaccinated employees as well as those who have recently recovered from COVID-19.

"We expect the measure will be in force for up to three weeks," Minister Vlastimil Valek told reporters, vowing to monitor "very carefully" the spread of Omicron.

The government will also trim the quarantine and isolation periods to five days each as of January 11, as it fears a rapid Omicron spread might reduce available workforce.

Czechs have until now been required to quarantine for one week, and isolate for two weeks.

"Omicron is a fast infection with a fast onset, this is why we have adopted the two measures," Valek added.

The Czech Republic led a global AFP tally of per capita COVID-19 deaths and infections in early 2021 and then last autumn.

Following a deceleration at the end of last year, daily infection rates have started to grow again in recent days.

The EU member of 10.7 million people has registered more than 2.5 million COVID-19 cases and almost 36,400 deaths.