Zhengzhou, capital of Henan province, on Aug 6 upgraded epidemic control measures after a recent resurgence of COVID-19 infections broke out in a local hospital.

Residents in the city's medium- and high-risk areas for COVID-19 should be quarantined at home, and people in control areas should not leave their community compounds, according to a notice from the city's epidemic prevention and control leading group.

Citywide, people are suggested to reduce movements and not to leave the city unless necessary. Intercity passenger bus services have been suspended and the frequency of urban bus departures has been reduced. Taxis and ride-hailing cars are not permitted to enter medium- and high-risk areas, and are only allowed to operate in urban areas, the notice said.

Venues such as public bathrooms, beauty salons, entertainment venues, offline training institutions and nurseries are temporarily closed. Dining in restaurants is also prohibited, it said.

Henan reported 21 locally transmitted confirmed COVID-19 cases and 102 asymptomatic cases from July 31 to Aug 5, the provincial health commission said on Aug 6.

By 6 pm on Aug 6, 118 infections－18 confirmed cases and 100 asymptomatic cases－had been reported in Zhengzhou.

Genome sequencing results show some cases are of the delta variant, and they are highly identical to imported cases receiving treatment at the Sixth People's Hospital of Zhengzhou, suggesting the latest outbreak in the city is sparked by hospital-acquired infections, officials with the National Health Commission said on Aug 5.

During an inspection in Zhengzhou, Vice-Premier Sun Chunlan reiterated that there should be zero tolerance for in-hospital infections, according to a media release on Aug 5.

Sun visited venues including the provincial center for disease control and prevention, a nucleic acid testing site, a residential community and the hospital where in-hospital infections occurred.

She urged accelerating investigations into key personnel like close contacts and conducting citywide nucleic acid testing. She said lessons must be drawn from in-hospital infections.

Residents in Zhengzhou are cooperating with the epidemic control measures. Zhang Jianguo, a manager of Jinganghui Network Technology in Zhengzhou, said that his company has suspended on-site conferences and is carrying out a flexible working schedule.

He said that though the tightened measures have made life inconvenient, he and his family remain confident that the outbreak will be brought under control in the near future.

"I have to admit I'm a little bit afraid of being infected, but I believe we will win the battle," he said.

Yan Dongsheng, director of the emergency department of Third Affiliated Hospital of Henan University of Traditional Chinese Medicine, who went to Wuhan, Hubei province, to assist the local fight against COVID-19 last year, said given the effective and rapid measures taken, he believes the expansion of the outbreak will be curbed.