Jeremy Farrar of the Wellcome Trust tells BBC Radio 4's Today programme Omicron is spreading "unbelievably fast" and transmission is "eyewateringly high".

His personal view is that society "can wait until there are more restrictions formally placed".

Meanwhile,  A man living in Texas is believed to be the first victim to died from Omicron variant of Covid-19 in the US, the media reported on Monday.

"A man in his 50s from the eastern portion of Harris County who was not vaccinated (has died)," Judge Lina Hidalgo tweeted. The victim had an underlying health condition, she added.

Reports from ABC News and Fox News said this is believed to be the first recorded Omicron-related death in the US.

Omicron accounts for 73.2 percent of new cases across the country in the week that ended on Dec 18, the US Centers for Disease Control and Prevention said.

(Reporting by Xinhua/UNI)