Professor Zhang Wenhong attends a live video streaming webcast about prevention of the virus on April 02, 2020 in Shanghai, China.

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Hong Kong CNN  — 

As the highly infectious Delta variant took hold in China last month, Zhang Wenhong, a well-respected infectious disease expert in Shanghai, told a concerned Chinese public to prepare to live with the coronavirus for the long haul — but his candor came at a price.

For more than a year, China had largely kept the virus at bay by tightly sealing its borders and swiftly taming local flare-ups with zero tolerance for infections. But despite stringent measures, a dozen cases of the Delta variant were detected among cleaning staff at one of the country’s busiest airports. The variant soon spread to more than half of China’s 31 provinces, resulting in excess of 1,000 infections in less than three weeks.

The rapid spread of Delta coincided with efforts to ramp up vaccinations. To date, 1.9 billion doses of domestic vaccines have been administered in China, according to the National Health Commission (NHC).

Writing on Chinese social media site Weibo, Zhang said it might not be possible for existing vaccines to completely eradicate Covid-19, and transmissions might still occur after everyone is fully vaccinated — albeit at a lower rate and causing fewer deaths.

“What we’ve been through is not the hardest part. What’s harder is finding the wisdom to coexist with the virus in the long run,” wrote Zhang, who has been repeatedly compared to US epidemiologist Anthony Fauci for being a widely trusted voice on the pandemic.

Learning to live with the virus is hardly an outrageous proposition. Most scientists believe Covid-19 is likely here to stay, and an increasing number of countries with high vaccination rates — such as Britain and Singapore — are opting for a strategy of coexistence, hoping it would eventually become a less dangerous endemic, like the flu.

But in China, Zhang’s remarks drew a torrent of attacks online, with detractors accusing him of refuting the country’s much touted zero-Covid strategy.

Some enraged nationalists called him a “traitor” who “blindly worshiped Western ideas.” Others alleged he was colluding with foreign forces to sabotage China’s Covid response. Still others sought to undermine his academic credentials, digging out his doctoral thesis published two decades ago and accusing him of plagiarism.

Shanghai’s prestigious Fudan University, where Zhang obtained his doctoral degree and teaches, said in a statement Sunday it had received complaints against Zhang and was aware of the online accusations about his thesis. It said it had launched an investigation to verify the claims.

The attack on Zhang underlined the highly politicized nature of discussions around China’s Covid-19 strategy.

Since China curbed its initial outbreak, the ruling Communist Party has held up the country’s effective containment efforts as proof of the supposed superiority of its authoritarian political system. The success of its zero-Covid strategy is hailed as an ideological and moral victory over the faltering response of the US and other Western democracies, which had struggled to control surging cases and deaths.

People wear face masks on the subway amid the Delta variant outbreak on July 27 in Nanjing, Jiangsu Province of China.

Those political overtones were highlighted in a commentary published on August 7 by party mouthpiece the People’s Daily. In the article, former health minister Gao Qiang attacked the idea of “coexisting with the virus,” accusing the US and Britain of “disregarding people’s health and safety” and causing a resurgence of outbreaks.

“This is a mistake in Covid decision-making caused by the defects in the political systems of countries like the US and the UK, as well as an inevitable result of advocating individualistic values,” wrote Gao, who was trained as an economist.

Without naming Zhang, the former minister said he was surprised to see some Chinese experts advocating for the coexistence approach.

Gao’s article has further fueled nationalist fury against Zhang, while appearing to signal the government’s continued commitment to its zero-Covid approach.

This commitment appeared to be reinforced on August 11, when police detained a teacher in the eastern province of Jiangxi for 15 days for commenting on a news article saying the country can “coexist with the coronavirus,” according to a local government notice.

But still, many experts, scholars and supporters have rallied to Zhang’s defense.

Ning Yi, a public health expert, posted on Weibo a photo of himself and Zhang in support, commenting: “If we can’t protect an expert as selfless as Zhang Wenhong, then our society is doomed.”

Yan Feng, a Chinese literature professor at Fudan University, warned of the potential chilling effect of the political witch hunt against Zhang. “Who will dare to speak out, who will dare to take responsibility, who will act according to their professional judgment in the future?” he asked.

Some Weibo users said the attacks on Zhang are reminiscent of the Cultural Revolution, during which scientists — along with intellectuals and artists — were subject to public humiliation and savage attacks by the Red Guards for their perceived political unreliability.

This isn’t the first time Zhang has drawn the ire of Chinese nationalists, who are increasingly dominating China’s social media by attacking and silencing more liberal and moderate voices. Last year, he was accused of pandering to Western lifestyles when suggesting kids should have eggs and milk for breakfast for protein instead of traditional Chinese rice porridge.

Jin Dongyan, a virologist at the University of Hong Kong, said the rapidly shrinking space for public discussion on epidemic control strategy is concerning.

“Experts involved in decision making should be encouraged to communicate with the public, and different opinions should all have channels to speak up,” he said. “From a public health perspective, it is unhealthy and outright dangerous to only allow one kind of voice.”

In recent days, China’s local confirmed cases dropped to the single digits — a possible indicator that its zero-Covid containment measures are working on the Delta variant.

And on Wednesday, Zhang broke three weeks of silence on Weibo, updating his 3.8 million followers on his recent work. In an apparent attempt to allay fears that he had been pressured into silence, Zhang said he doesn’t post on Weibo often, and that he decided to post again because many people had expressed concerns for him.

He also tried to walk back on his earlier call for China to learn to coexist with the virus.

“The Covid-19 strategy our country has adopted is one that suits us the best at present,” he wrote. “You have to try the shoes on yourself to know whether they fit properly.”