China insists its zero-Covid strategy is correct. Challenging it can be dangerous

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.