China's top leaders on Thursday hailed the "miracle" of the country's zero-Covid reversal, calling the dramatic turn away from hardline virus curbs a "major decisive victory" and "completely correct", according to state media.

A torrent of infections engulfed the world's most populous nation after the government did away with some of the world's tightest virus containment measures late last year.

The surge packed hospitals and crematoriums in major cities including Beijing, but the outbreak's true scale is hard to quantify as official data is believed to represent a tiny fraction of the actual number of cases.

There have been signs in recent weeks that the wave is finally receding, with the country's disease control bureau saying Wednesday that the number of people receiving Covid care in hospitals had declined by over 98 percent since early January.

A meeting of the Politburo Standing Committee -- the apex of Communist Party power -- affirmed Thursday that China "created a miracle in the history of human civilisation in which a country with a large population successfully emerged from a widely circulating epidemic".

"In a relatively short period of time, we have achieved a smooth transition in epidemic prevention and control," concluded the meeting attended by President Xi Jinping, according to state news agency Xinhua.

More than 200 million people had been treated for Covid including 800,000 critically ill patients, but the situation was now "generally trending for the better", the report cited the participants as saying.

They agreed the party's policy change was "completely correct", it said, adding: "The measures have been strong, the masses have approved of them, and the results have been huge."