Without a 'zero Covid' policy exit strategy, China could face a tsunami in some cases, experts fear

Without a ‘zero Covid’ policy exit strategy, China could face a tsunami in some cases, experts fear

AAs the world watches the rare spectacle of protesters challenging China’s authoritarian leadership over its increasingly confusing “zero Covid” policy, people who study the disease see threats to China — and beyond.

The zero Covid policy, which has kept China’s cases and deaths negligible throughout the pandemic, appears doomed in the face of the highly transmissible Omicron variant of the SARS-CoV-2 virus, say- they. But Chinese leaders do not appear to be charting a course for a safe exit ramp, leaving experts worried the country could see a tsunami of cases that would overwhelm its health system if the national containment effort collapses.

“I think they are very ill-prepared and from what we saw in Hong Kong – which is probably the best indicator of what could happen in China – it could be quite devastating,” said Francois Balloux, Director of Genetics at University College London. Institute, told STAT in an interview.


Hong Kong has also adopted a zero Covid policy, employing draconian quarantine, tracing and testing policies to try to stop transmission of the virus. For more than two years, this system protected the city from disease. But in the spring, Omicron entered Hong Kong, dramatically increasing the number of infections there.

The same pattern could play out in mainland China, said Ben Cowling, an infectious disease epidemiologist at the University of Hong Kong.


“If this is not stopped, we will see a lot of infections in cities that have outbreaks. It will be like the experience of Hong Kong earlier this year, where we had half the population infected in the space of about a month or two,” he said.

Cowling was participating in a roundtable discussion on a Monday night podcast about developments in China. One of the Chinese panelists was very optimistic about zero Covid, saying it had prevented China from suffering the losses that countries like the United States have suffered. China has recorded just over 5,200 Covid deaths since the start of the pandemic; the United States recorded more than a million.

“I wanted to ask: How much would you pay for zero Covid? Because the price goes up and up and up,” Cowling said. “A year ago it made a lot of sense. I think it was a very profitable strategy in China, just like in Singapore. But… it gets harder and harder to maintain, and there has to be a point when you start to think the cost isn’t justified anymore, or you don’t have the money to pay for it.

A number of countries – including Australia, New Zealand and Singapore – also adopted a zero Covid policy earlier in the pandemic, limiting entry to people who had been quarantined and tested negative for the disease. But most zero Covid countries have used the policy to buy time until vaccines are developed and rolled out. Once their populations were protected, they emerged from restrictive policies.

China, however, appears to believe it can fend off the virus indefinitely. As cases soar to levels never seen before – around 40,000 a day for the past few days – experts who have tracked the trajectory of the virus across the rest of the world are shaking their heads at what they see it as an unattainable goal.

Marion Koopmans, a virologist and head of the viroscience department at Erasmus Medical Center in Rotterdam, the Netherlands, feared the protests could further fuel the spread of Covid in China.

“The cat will be out of the box,” Koopmans said. “It could then lead to – depending on what China does, how China reacts – but it could lead to a really big wave, if it gets out of control.”

The immunity status of the Chinese population amplifies the concern of people like Koopmans. The country quickly developed a number of vaccines, although it relied mainly on inactivated vaccines, which use some or all of the killed viruses to trigger an immune response. These vaccines work, but are not considered as potent as the messenger RNA vaccines that most Western countries have relied on.

Cowling said three doses of inactivated vaccines – made by Sinovac and Sinopharm – protect quite well against serious infections and death. But while a high percentage of people have had a primary series, which consists of two shots, it’s estimated that only about half the country has had a third. Booster uptake in older people is low, and many of those who received a third injection did so nine months or a year ago, suggesting their protection may be waning, Balloux said.

And paradoxically, the very fact that the Chinese authorities have protected their people from Covid for so long now makes them more vulnerable to the disease.

In countries where Covid has spread largely unchecked since the rollout of vaccines, many people have developed what is known as hybrid immunity. In addition to having been exposed to three, four, even five doses of vaccine, their immune system has encountered the SARS-2 virus, expanding the scope of their immunological defenses. Few people in China benefit from the additional protection that vaccination and infection generate.

“There will be some protection. It wouldn’t be like 2020 in some parts of the world,” Cowling said of what would happen if China couldn’t contain the infection. “But there would be a lot of severe cases, unfortunately…and China doesn’t have a very robust healthcare system to handle a lot of severe cases.”

Even though the Omicron strain of the virus is less severe than, say, the Delta variant that preceded it, it is more contagious. With so many susceptible people, the number of cases could be huge.

Some people openly speculate that the fact that SARS-2 passes through such large numbers of people could fuel the emergence of new variants with an even greater ability to evade accumulated immunity than individual subvariants. ‘Omicron.

Koopmans thought that was a possibility. “It’s a whole new chapter, and a generic chapter that potentially unfolds,” she said. She noted, however, that the lack of broad immunity in China could argue against this, given that one of the main triggers of viral evolution is the virus’s need to acquire means of escaping. human immunity.

“The good thing, if you can call it that, is if there’s not so much immunity wall, then there’s not so much selection pressure. [on the virus]said Koopmans. “So that might work against a new selection of variants.”

Cowling also noted that there is a lot of continued circulation of SARS-2 elsewhere that could trigger the emergence of new variants.

Virus evolution is not the only threat, however, that a failure of the zero Covid policy – ​​or lack of controlled exit – could pose. The supply chain issues that have plagued the world through the pandemic could be exacerbated if China faces a major wave of Covid.

A number of large companies are already experiencing major difficulties with Chinese supplies, “and that could only make matters worse,” said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, which has a program in which experts liaise with businesses on the implications of infectious disease outbreaks.

China is a major drug producer and exporter of key drug ingredients. Osterholm, who has studied supply chain vulnerabilities for years, said that of 153 lifesaving drugs used in the United States, all are made in China or rely on active pharmaceutical ingredients from China.

He, too, is worried about how China will find a solution to its zero Covid dilemma, suggesting leaders may be overly reassured by how the country has weathered the waves caused by the Alpha and Delta variants.

“Alpha and Delta were more like putting out severe forest fires. Difficult but doable. Releasing Omicron and its sub-variants is like trying to stop the wind,” Osterholm said.

” You can not. You can divert it but you cannot stop it.

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