The world needs to ‘calm down’ about the risk of a new COVID variant emerging from China, the country’s former CDC chief says

“The world should completely calm down from the fear that there are new variants or special variants circulating” in China, George Gao, professor at the Institute of Microbiology at the Chinese Academy of Sciences and former head of the Chinese Center for Disease Control and Prevention, told Reuters on Wednesday.

A study published in The Lancet on Wednesday by Gao and colleagues, including several from the Beijing Center for Disease Prevention and Control, found no evidence of new variants among 413 genetically sequenced samples collected between Nov. 14 and Dec. 20, 2022.

“Although our data were only from Beijing, the results could be considered a snapshot of China, due to the frequent population exchange and the presence of circulating strains with high transmissibility,’ the authors wrote.

Experts have eyed China for the potential evolution of new variants, given its massive population and widespread lack of COVID exposure, prior to the relaxing of restrictions in December. Rampant COVID spread gives the virus a statistically better chance of spawning a new, more dangerous variant, many scientists have said.

Dr. Amesh Adalja, an infectious disease specialist and senior scholar at the Johns Hopkins Center for Health Security, agrees with Gao. COVID variants evolve to evade population immunity—something China hasn’t had, he tells Fortune.

So “it’s not surprising that no concerning variants arose there, despite media speculation,” Adalja says. “The data from China is backed up by surveillance of individuals who have traveled to China, showing these variants to be well characterized versions of Omicron that are not particularly concerning.”

But not all experts agree. Dr. Bruce Y. Lee, professor of health policy and management at the City University of New York School of Public Health, tells Fortune that concerns of a new variant arising from China are valid, given intense circulation—and that the country could dispel anxiety by simply being more forthcoming on the topic.

“Rather than tell the world to ‘calm down,’ it would be much better for China’s government to be much more open about sharing its COVID-19 surveillance data and methods with the rest of the world,” Dr. Bruce Y. Lee, professor of health policy and management at the City University of New York School of Public Health, tells Fortune.

World Health Organization officials have repeatedly implored China to be more forthcoming about the pandemic’s origins and viral activity within the country. And they’ve frequently accused the country of providing an incomplete picture of cases and deaths there.

Dr. Ryan Gregory—a COVID variant tracker and biology professor at the University of Guelph in Ontario, Canada, who has been assigning “street names” like “Kraken” to “high-flying” COVID variants like XBB.1.5—tells Fortune that the sample examined in Gao’s study is “hardly” representative. While it’s estimated that a billion Chinese have been infected since December, the study only looks at a few hundred cases over one month, in one city.

Lee agrees with Gregory, telling Fortune it’s unlikely that the study’s sample is “large or diverse enough to determine whether there may be new variants circulating in China.”

“As we’ve seen in the U.S., new variants and and subvariants do not spread equally throughout a geographic area at a given time,” he adds. “Conclusions based on sample mainly from Beijing would be like conclusions based on samples mainly from Los Angeles.”

“It is difficult to imagine 413 cases being enough to cover the true diversity that exists in China.”

What’s more, a new variant from China would not be expected to show up so soon, Ryan says: “The issue is what evolves there now.”

While it’s “unreasonable to single out China” as the world’s sole threat when it comes to COVID evolution, “it would be equally foolhardy to pretend that variants aren’t evolving there,” he adds. “This study certainly doesn’t provide strong evidence that nothing new is emerging in China.”

While Gao’s study has a comforting takeaway, “it doesn’t mean we should let our guard down,” Dr. Georges Benjamin, executive director of the American Public Health Association, tells Fortune.

“New variants can occur at any time, and China is a big country with an outbreak that is still robust,” he says. “The risk is not over yet.”

Dr. Michael Merson, visiting professor at New York University’s School of Global Public Health, echoes Benjamin’s comments, saying that the study’s findings were “somewhat reassuring.”

But he hopes they will soon be “supplemented by an analysis of variants from areas other than Beijing and over a longer period,” he adds.

Triton and Minotaur currently dominating China

Omicron subvariants BA.5.2, dubbed “Triton,” and BF.7, dubbed “Minotaur,” accounted for 90% of sequenced cases in Gao’s study. Both are spin-offs of BA.5, which dominated globally this summer. BA.5 and its descendants continue to dominate globally but are on the decline, according to the WHO.

The duo of variants accounted for nearly 98% of locally acquired infections from Dec. 1 through early January, based on 2,000 sequenced samples, representatives of China’s CDC told WHO officials Jan. 4. The data aligned with that submitted by other countries that sequenced samples from travelers inbound from China, the WHO said at the time. “No new variant or mutation of known significance is noted in the publicly available sequence data,” it added.

Globally, 10.5 million new cases of COVID, and more than 90,000 COVID deaths, were reported over the last 28 days, the WHO said in a Wednesday report, adding the numbers are undoubtedly underestimated. Recent reports of cases and deaths have been fueled by the Western Pacific region, namely China, the report noted.

Of the more than 70,000 COVID sequences shared globally over the past month, more than 99.6% were Omicron strains, according to the WHO.

As Fortune previously reported, an estimated 900 million Chinese have been infected with COVID as of Jan. 11, according to a recent study. Japan, too, recently saw its darkest days of the pandemic, when back-to-back waves of Omicron strain BA.5 caused deaths there to skyrocket to an all-pandemic high.