(Bloomberg) -- New Covid cases in Beijing jumped to the highest level in more than five months, with officials alarmed by infections being found outside of quarantine that show the virus is still spreading in the community. 

China’s capital reported 78 new infections Wednesday, the most since May 22. The city has reported double-digit daily cases for most of the past month, though numbers started to spike in recent days, doubling from 39 on Nov. 4. 

Six infections were found outside of isolation facilities, up from one the day before. China, which automatically quarantines anyone with a confirmed case and their close contacts, monitors community transmission as a key indicator of whether an outbreak is under control. While the numbers are small by global standards, with much of the world now living with Covid, they’re high for a country that is continuing to try and eliminate the virus. 

“Beijing continues to find cases through community testing, which shows that risks of hidden transmissions in the community persist,” Liu Xiaofeng from the Beijing Center for Disease Control told reporters at a briefing Tuesday. That was a change from a day before when another CDC official said that the capital has effectively controlled most transmission chains through fast and scientific virus controls and the cooperation of the public. 

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More than 10 buildings and neighborhoods in Beijing’s central Chaoyang district, where most of the cases have been found, were locked down. Residents can’t leave their homes or housing complexes unless they’re getting a Covid test, and more than 4,400 Communist Party cadres have been dispatched to assist with the needs of those under lockdown, according to a district official.

Testing frequency has been increased to once a day, for up to five days this week for several districts including Chaoyang, Haidian and Changping. With the outbreak concentrated in Chaoyang, some residents there reported being sent to quarantine centers after receiving abnormal test results that could indicate Covid infections. However, some schools, day care centers and kindergartens that closed earlier in the week were able to reopen after infection risks have been eliminated.

Biggest Outbreak

The nation’s biggest outbreak is in Guangdong province, which is the main driver of the national caseload rising to 7,740 on Tuesday, the highest tally since April 29. Most infections are in the southern metropolis of Guangzhou, which reported 2,637 cases. It locked down two more districts on Wednesday, bringing the total to three out of 11. 

Concerns are growing that Guangzhou could be headed for a Shanghai-style situation, with cases snowballing in the face of more targeted restrictions. Some residents Bloomberg News spoke to have tried to order items like toilet paper, medicine and instant noodles in bulk, but have been impeded by disruptions to courier services from the lockdowns. Those in the districts where stay-at-home orders were imposed are still able to go out for groceries and essentials.

The swelling outbreaks show the strain China’s Covid Zero strategy is facing, with harsh lockdowns and constant mass testing failing to quickly contain them. Health officials over the weekend reaffirmed the country’s unswerving commitment to the policy, even as it hammers the economy, dashing hopes that authorities will soon move toward easing some of their strictest rules.

This Is How Long Experts See China Clinging on to Covid Zero

Meantime, a weeklong lockdown in one of Zhengzhou’s districts has ended, though the world’s largest iPhone assembly plant is located in an area that will continue to face strict curbs.

(Adds lockdown of third district in the seventh paragraph)

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