It will take a period of time to find out how harmful the new COVID-19 variant Omicron is and it is too early to reach a conclusion about it yet, China's top epidemiologist Zhong Nanshan said Sunday.

The variant, first detected in South Africa earlier this week, is very new, Zhong told reporters at a respiratory disease conference in Guangzhou City, south China's Guangdong Province. 

Although molecular genetic tests have shown it has many mutations on its receptor binding domain, which is the part that the virus uses to get into human cells, it will still take some time to know how fast it can spread, whether it will cause more severe illness, and whether new vaccines are needed to target it, Zhong said.

He added that close attention should be paid to the new variant, but no big moves will be taken for the moment in China.

He also noted that prevention and control measures should be taken against travelers from South Africa and nearby regions.

Global authorities have reacted with alarm to the new strain, with the EU, Britain, India and Israel among those announcing stricter border controls.

Read more: New COVID-19 variant spreads, countries on high alert

Two weeks needed for more observation

Zhong's remarks were echoed by Zhang Wenhong, another leading infectious disease specialist in China who heads Shanghai's COVID-19 medical team.

In a post on China's Twitter-like social media platform Weibo on Sunday, Zhang said the world will need two weeks to observe data from global labs and make an accurate judgement on whether the new variant means global anti-pandemic efforts have been in vain.

China's zero-COVID policy will protect against all variants

Zhang added the new variant will not have a big impact on China at present, as the country's rapid response and dynamic zero-COVID strategy can protect it against all kinds of COVID-19 variants.

"No matter how SARS-CoV-2 (the virus that causes COVID-19) changes, it's still SARS-CoV-2," he wrote, adding that China's zero-COVID strategy has won it a "strategic opportunity" as the new variant forces other countries to begin reimposing restrictions.

China is accelerating building up scientific tools – including reserves of effective vaccines, drugs, as well as public health and medical resources – that can support the country's opening up to the world and normalized epidemic control and prevention measures in the next stage, he wrote.

"With science and solidarity, we can handle the Omicron variant, just as we have contained the Delta variant," he wrote.