(Bloomberg) --

China put 400,000 residents of a northern county under lockdown over the weekend after at least a dozen coronavirus cases associated with the Beijing outbreak were reported there.

In a sign that the resurgence of cases in the capital is proving difficult to stamp out even as officials say they’ve been largely contained, Hebei province’s Anxin county has been sealed off and each household can assign only one person to go out for necessities daily, reported state media. Vehicles cannot enter the county and only those with special passes can leave.

The containment measures in Anxin, located 140 km from Beijing, are more severe than in the capital itself where the cluster has grown to 311 people since it was first detected on June 12. While schools are closed and transport limited in Beijing, people are still allowed to leave as long as they have a negative virus test.

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The aggressive measures taken to contain the spread in Anxin reflect the challenges faced by governments around the world as they try to prevent flare-ups from growing into second waves of infection. China has strenuously avoided a full lockdown of the capital to minimize disruption in its political and cultural center, and has relied on rapid testing to stem the outbreak.

Beijing, which can test 3.8 million samples daily, is still reporting several new infections every day although the country’s top epidemiologist said on June 19 that the outbreak had come under control. How the virus came roaring back in the city after 55 days without any cases is still a mystery.

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The pathogen was traced to the chopping board of a salmon vendor in the biggest Beijing wholesale market, Xinfadi, sparking a nationwide boycott of the seafood. Over 2,100 people from Anxin county do seafood-related business in Xinfadi, state media reported, citing municipal government officials.

Six months after the virus first emerged from China, the coronavirus has sickened over 10 million people and killed more than 500,000 and the pandemic is gaining new momentum in the Americas.

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