The head of the World Health Organization said on Wednesday he was “very concerned” about an unprecedented surge of Covid cases in China, as the health agency urged Beijing to speed up vaccination of those most at risk.

The evolving situation in China, with increasing reports of serious illnesses,” Tedros Adhanom Ghebreyesus said at a weekly news conference, asking for detailed information on the severity of the illness, hospital admissions and critical care requirements.”

The highest risk nationwide, and we continue to offer our support to provide clinical care and protect their healthcare system,” he added. Since 2020, China has imposed strict hygiene restrictions as part of the so-called “zero Covid” policy.

But the government ended most of these measures without warning in early December amid mounting public anger and a significant blow to the economy.

Since then, the number of cases has skyrocketed, raising fears of a high mortality rate among the elderly, who are particularly at risk. Chinese authorities said on Tuesday only those who died directly from respiratory failure caused by the virus were counted.

Under the Covid death statistics. The change in criteria for recording virus deaths means most are no longer counted, and China said on Wednesday not a single person had died from Covid-19 the previous day.

WHO chief for emergencies Michael Ryan stressed the need for more vaccines: “We have been saying for weeks that it would always be very difficult to completely stop this highly infectious virus with only public health and societal measures.” And most countries have really moved to a mixed strategy.”

“Vaccination in this sense is the exit strategy from the effects of an omicron wave”, the dominant variant of Covid.