South Africa is preparing its hospitals for more admissions, as the Omicron coronavirus variant pushes the country into a fourth wave of COVID-19 cases, President Cyril Ramaphosa said on Monday.

Omicron was first detected in southern Africa last month and has triggered global alarm as governments fear another surge in infections.

South Africa's daily infections surged last week to more than 16,000 on Friday from roughly 2,300 on Monday.

Ramaphosa said in a weekly newsletter that Omicron appeared to be dominating new cases in most of the country's nine provinces and urged more people to get vaccinated against COVID-19.

"South Africa now has sufficient supplies of vaccines, … vaccination is essential for our economic recovery because as more people are vaccinated more areas of economic activity will be opened up," he said.

The government would soon convene the National Coronavirus Command Council to review the state of the pandemic and decide whether further measures are needed to keep people safe, Ramaphosa said.

Scientists in South Africa and other countries are racing to establish whether Omicron is more contagious, causes more severe disease and is more resistant to existing vaccines.

But some anecdotal accounts from doctors and experts in South Africa are reassuring, suggesting that many infections it causes are mild.

"We are keeping a close eye on the rates of infection and hospitalization," Ramaphosa said.