What China’s Zero-COVID Policy Means for the Pandemic—in China and the Rest of the World

Protests in multiple Chinese cities over the strict COVID-19 policies enforced by China’s government reflect the growing sentiment of people around the world. We’re tired of the pandemic, and tired of the myriad ways the SARS-CoV-2 virus has changed our lives forever. But the demonstrations in China also reflect a more specific, local frustration with a strategy for controlling the virus that every other country in the world has long since left behind.

China’s zero-COVID strategy is an extension of the drastic measures instituted, not only in that country but in others around the world, including the U.S., during the early days of the pandemic in an effort to quash the virus as quickly as possible. That made sense at the beginning when people had no immunity to the virus, and there were no vaccines or treatments to fight it. In fact, instituting lockdowns and keeping people from mingling are among the public health pillars of controlling an infectious disease. “Employing quarantine, isolation, and testing are all core public health strategies that we use in all sorts of outbreaks,” says Caitlin Rivers, an epidemiologist at Johns Hopkins Center for Health Security. “And they remain viable. But they don’t always infringe on basic freedoms and rights in the same way we have seen in China. Clearly in this instance, they have become very extensive.”

China’s strategy has been to test people regularly before they leave their residences, or enter public facilities, and when anyone tests positive, to immediately quarantine the facility where the case arose, even if it means preventing people from returning home from work or from a daytrip Disneyland. From there, people who test positive are transferred to isolation facilities where they remain until they produce negative tests before they are allowed to return home.

But while chasing after the virus in this way can limit its spread, such stalking can only go so far. Ultimately, the virus escapes, and new infections are seeded. In SARS-CoV-2’s case, that likelihood is increased by the fact that the virus also lives in animal hosts where it continues to thrive, and mutate, waiting for opportunities to infect vulnerable human hosts with little defensive immunity against it. “It’s difficult to envision how a zero-COVID policy would eradicate this virus,” says Dr. Ian Lipkin, director of the center for infection and immunity at Columbia Mailman School of Public Health. “Even if you exclude all human beings from being hosts, there are still animal reservoirs capable of carrying the virus, and reintroducing it into human populations.”

While other countries, including Australia, the U.K., and the U.S. instituted a quarantine system similar to China’s in the early days of the pandemic, health officials there always acknowledged it would be a temporary solution, until the population’s immunity could be bolstered, both from exposure to natural infections and ultimately by vaccines.

For China, however, the strategy has been inflexible, and without a clearly defined exit strategy—largely because of how tightly intertwined it is with the authority and stature of the ruling Chinese Communist Party. “Politically, the pandemic response has been framed as a competition between two political systems, and Xi Jinping used China’s early success to showcase the superiority of the Chinese political system,” says Yanzhong Huang, senior fellow for global health at the Council on Foreign Relations, and professor of global governance and health issues in Asia at Seton Hall University. “”Theoretically, if they are able to sustain a low level of infection after other countries have moved away from zero COVID policies, they could claim they are the only winners in the fight. So the high political stakes also contributed to China keeping these policies.”

Meanwhile, for the rest of the world, when effective vaccines became available at the end of 2020, a zero-tolerance strategy quickly became obsolete. As a population’s protection against the virus mounts due to immunizations, then confining infected people and trying to shut down large regions becomes no longer necessary. That’s the approach that Australia took, after a zero-COVID policy at the beginning of the pandemic. But, says Rivers, the difference was that Australia set a limit to the strict lockdowns, promising to lift them when 80% of the population had been vaccinated and therefore were better protected against severe disease. “There needs to be an exit strategy,” she says. “Australia clearly defined that strategy to keep the public on board and understand what the path forward was. It was also important to make sure the country didn’t get stuck in an unsustainable place.”

China may be in such a situation, with no clearly articulated end to its current policy.

The threats to global public health posed by China’s policy

Keeping people isolated does give the virus fewer opportunities to spread and infect locally, but in a worldwide pandemic, that may not be the most desirable end result. People who are inadequately vaccinated, or who haven’t had much exposure to natural infection with the virus, fail to generate strong T-cell responses, which scientists believe is important for longer-lasting protection against serious COVID-19 disease. Much of the rest of the world has been building this T-cell defense, due to a combination of vaccination, boosting, and exposure to and infection with COVID-19. China’s population may still be in the nascent stages of amassing this type of protection. “Basically they have a population that is inadequately protected by either earlier infection or vaccination, who are now at risk for spread of the virus,” says Lipkin.

Contributing to that is the fact that studies show that the vaccines taken by the majority of China’s population, made in-country by two local companies, Sinovac and Sinopharm, haven’t provided as much protection against infection or severe disease as those produced in the U.S. and Europe. Those vaccines use inactivated forms of the SARS-CoV-2 virus to stimulate the immune system, while other approaches have utilized new mRNA or viral vector technologies. That means that China’s population, although it may be immunized, may not be as protected as they could be. Indeed, Lipkin says that were China to deploy vaccines like the mRNA shot from Pfizer-BioNTech and Moderna, or the viral vector vaccines from AstraZeneca, as booster shots, it could improve the protection begun by the inactivated virus vaccines the Chinese have used to date. Chinese scientists have been working on these other types of vaccines, including mRNA shots, but the health leadership has not yet endorsed these for widespread use in the country.

Then there is the human and economic toll of quarantining people, cutting them off from and disrupting their social, professional, and cultural connections. The result has been that pent up frustrations have erupted into protests against not just the restrictive COVID-19 policies, but the entire communist system in recent weeks, in a stunning and rapidly spreading movement. “I think the Party was caught off guard when they were seeing protests in multiple cities,” says Huang.

How to take the next step forward

Health experts agree that the path out of zero-COVID is to accelerate vaccination of the population, which Chinese leadership has been attempting to execute in recent weeks. Party officials are fighting a problem of their own making, however, as many elderly members of the population have not been immunized because they don’t feel the urgency in a country where cases had been relatively low given the strict lockdowns. In a report released on Nov. 28, government health officials in China said 65.8% of people over age 80 years had received a booster dose. That’s an increase from the 40% reported in the middle of the month—but still far too low.

Even if more people are boosted, given the waning protection provided by those shots, especially against newer Omicron variants, such boosters may not be enough to bolster the population’s immunity to levels that would justify phasing out the zero COVID policy. As long as the virus is able to produce more copies of itself, it will continue to evolve and generate new mutations, some of which could become variants that spread more quickly or cause more severe disease. The roulette wheel of viral mutations continues to spin, and the best defense to slow it down is through immunity—either from vaccinations or bouts of infections.

“China has a population with very little infection-acquired immunity. And the vaccine acquired immunity has not held up well over time against new variants,” says Rivers. “So we expect a population that is largely susceptible. And those are conditions for large waves of infections. From a public health perspective, I would expect widespread vaccination and boosting of older people. But that is as much a political question as a public health one.”