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China’s COVID Wave Is Coming

For now, the forecast “is full of ifs and buts and maybes,” says Salim Abdool Karim, an epidemiologist at the Centre for the AIDS Programme of Research in South Africa. Perhaps the worst can be averted if the government does more to vaccinate the vulnerable and prep hospitals for a protracted influx of COVID patients; and if the community at large reinvests in a subset of mitigation measures as cases rise. “There is still the possibility that they may muddle through it without a mass die-off,” says Yanzhong Huang, a senior fellow for global health at the Council on Foreign Relations. “But even the most smooth and orderly transition,” he told me, “will not prevent a surge of cases.”

China represents, in many ways, SARS-CoV-2’s final frontier. With its under-vaccinated residents and sparse infection history, the nation harbors “a more susceptible population than really any other large population I can think of,” says Sarah Cobey, an computational epidemiologist at the University of Chicago. Soon, SARS-CoV-2 will infiltrate that group of hosts so thoroughly that it will be nearly impossible to purge again. “Eventually, just like everyone else on Earth, everyone in China should expect to be infected,” says Michael Worobey, an evolutionary virologist at the University of Arizona.

[Read: How many COVID deaths will Chinese protesters accept?]

Whatever happens, though, China’s coming wave won’t recapitulate the one that swept most of the world in early 2020. Though it’s hard to say which versions of the virus are circulating in the country, a smattering of reports confirm the likeliest scenario: BF.7 and other Omicron subvariants predominate. Several of these versions of the virus seem to be a bit less likely than their predecessors to trigger severe disease. That, combined with the relatively high proportion of residents—roughly 95 percent—who have received at least one dose of a COVID vaccine, might keep many people from falling dangerously ill. The latest figures out of China’s CDC marked some 90 percent of the country’s cases as asymptomatic. “That’s an enormous fraction” compared with what’s been documented elsewhere, says Ben Cowling, an epidemiologist at the University of Hong Kong.

That percentage, however, is undoubtedly increased by the country’s ultra-rigorous testing practices, which have been catching silent cases that other places might miss. All of Omicron’s iterations also remain capable of triggering severe disease and long COVID. And there are still plenty of worrying omens that climbing cases could reach a horrific peak, sit on a prolonged plateau, or both.

One of China’s biggest weak spots is its immunity, or lack thereof. Although more than 90 percent of all people in the country have received at least two COVID shots, those over the age of 80 were not prioritized in the country’s initial rollout, and their rate of dual-dose coverage hovers around just 66 percent. An even paltrier fraction of older people have received a third dose, which the World Health Organization recommends for better protection. Chinese officials have vowed to buoy those numbers in the weeks ahead. But vaccination sites have been tougher to access than testing sites, and with few freedoms offered to the immunized, “the incentive structure is not built,” says Xi Chen, a global-health expert at Yale. Some residents are also distrustful of COVID vaccines. Even some health-care workers are wary of delivering the shots, Chen told me, because they’re fearful of liability for side effects.

Regardless of the progress China makes in plugging the holes in its immunity shield, COVID vaccines won’t prevent all infections. China’s shots, most of which are based on chemically inactivated particles of the 2020 version of SARS-CoV-2, seem to be less effective and less durable than mRNA recipes, especially against Omicron variants. And many of China’s residents received their third doses many months ago. That means even people who are currently counted as “boosted” aren’t as protected as they could be.

All of this and more could position China to be worse off than other places—among them, Australia, New Zealand, and Singapore—that have navigated out of a zero-COVID state, says Caitlin Rivers, a senior scholar at the Johns Hopkins Center for Health Security. Australia, for instance, didn’t soften its mitigations until it had achieved high levels of vaccine coverage among older adults, Rivers told me. China has also clung to its zero-COVID philosophy far longer than any other nation, leaving itself to contend with variants that are better at spreading than those that came before. Other countries charted their own path out of their restrictions; China is being forced into an unplanned exit.

What Hong Kong endured earlier this year may hint at what’s ahead. “They had a really, really bad wave,” Kayoko Shioda, an epidemiologist at Emory University, told me—far dwarfing the four that the city had battled previously. Researchers have estimated that nearly half the city’s population—more than 3 million people—ended up catching the virus. More than 9,000 residents died. And Hong Kong was, in some respects, in a better place to ease its restrictions than the mainland is. This past winter and spring, the city’s main adversary was BA.2, a less vaccine-evasive Omicron subvariant than the ones circulating now; officials had Pfizer’s mRNA-based shot on hand, and quickly began offering fourth doses. Hong Kong also has more ICU beds per capita. Map a new Omicron outbreak onto mainland China, and the prognosis is poor: A recent modeling paper estimated that the country could experience up to 1.55 million deaths in the span of just a few months. (Other analyses offer less pessimistic estimates.)

Lackluster vaccination isn’t China’s only issue. The country has accumulated almost no infection-induced immunity that might otherwise have updated people’s bodies on recent coronavirus strains. The country’s health-care system is also ill-equipped to handle a surge in demand: For every 100,000 Chinese residents, just 3.6 ICU beds exist, concentrated in wealthier cities; in an out-of-control-infection scenario, even a variant with a relatively low severe-disease risk would prove disastrous, Chen told me. Nor does the system have the slack to accommodate a rush of patients. China’s culture of care seeking is such that “even when you have minor illness, you seek help in urban health centers,” Huang told me, and not enough efforts have been made to bolster triage protocols. More health-care workers may become infected; patients may be more likely to slip through the cracks. Next month’s Lunar New Year celebration, too, could spark further spread. And as the weather cools and restrictions relax, other respiratory viruses, such as RSV and flu, could drive epidemics of their own.

That said, spikes of illness are unlikely to peak across China at the same time, which could offer some relief. The country’s coming surge “could be explosive,” Cobey told me, “or it could be more of a slow burn.” Already, the country is displaying a patchwork of waxing and waning regulations across jurisdictions, as some cities tighten their restrictions to combat the virus while others loosen up. Experts told me that more measures may return as cases ratchet up—and unlike people in many other countries, the Chinese may be more eager to readopt them to quash a ballooning outbreak.

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A major COVID outbreak in China would also have unpredictable effects on the virus. The world’s most populous country includes a large number of immunocompromised people, who can harbor the virus for months—chronic infections that are thought to have produced variants of concern before. The world may be about to witness “a billion or more opportunities for the virus to evolve,” Cowling told me. In the coming months, the coronavirus could also exploit the Chinese’s close interactions with farmed animals, such as raccoon dogs and mink (both of which can be infected by SARS-CoV-2), and become enmeshed in local fauna. “We’ve certainly seen animal reservoirs becoming established in other parts of the world,” Worobey told me. “We should expect the same thing there.”

Then again, the risk of new variants spinning out of a Chinese outbreak may be a bit less than it seems, Abdool Karim and other experts told me. China has stuck with zero COVID so long that its population has, by and large, never encountered Omicron subvariants; people’s immune systems remain trained almost exclusively on the original version of the coronavirus, raising only defenses that currently circulating strains can easily get around. It’s possible that “there will be less pressure for the virus to evolve to evade immunity further,” says Emma Hodcroft, a molecular epidemiologist at the University of Bern; and any new versions of the virus that do emerge might not fare particularly well outside of China. In other words, the virus could end up trapped in the very country that tried to keep it out the longest. Still, with so many people susceptible, Cobey told me, there are zero guarantees.

Either way, viral evolution will plod on—and as it does, the rest of the world may struggle to track it in real time, especially as the cadence of Chinese testing ebbs. Cowling worries that China will have trouble monitoring the number of cases in the country, much less which subvariants are causing them. “There’s going to be a challenge in having situational awareness,” he told me. Shioda, too, worries that China will remain tight-lipped about the scale of the outbreak, a pattern that could have serious implications for residents as well.

Even without a spike in severe disease, a wide-ranging outbreak is likely to put immense strain on China—which may weigh heavily on its economy and residents for years to come. After the SARS outbreak that began in 2002, rates of burnout and post-traumatic stress among health-care workers in affected countries swelled. Chinese citizens have not experienced an epidemic of this scale in recent memory, Chen told me. “A lot of people think it is over, that they can go back to their normal lives.” But once SARS-CoV-2 embeds itself in the country, it won’t be apt to leave. There will not be any going back to normal, not after this.