Nanjing, Jiangsu province, reported 12 new locally transmitted COVID-19 cases and seven new asymptomatic carriers on Thursday.

A total of 23 patients with locally transmitted cases and 10 imported ones are receiving treatment at the city's designated hospital for the coronavirus, the provincial Health Commission said on Friday morning.

Fifteen local and 23 imported asymptomatic carriers were in a central quarantine facility and under medical observation as of early Friday morning, it said.

Neighboring Anhui province reported an asymptomatic case on Thursday, its health commission said on Friday.

The infected person, a 52-year-old man surnamed Tong, lives in Nanjing's Jiangning district and is the husband of a patient with a confirmed case discovered at Nanjing Lukou International Airport.

An interior decoration worker, Tong had been traveling by car between Nanjing and Hexian, Anhui, since June 30 until he tested positive in Hexian on Thursday morning, the provincial Health Commission said.

Shenyang, Liaoning province, Zhongshan, Guangdong province, and Liyang, Jiangsu, also reported locally transmitted cases involving people who had been to Nanjing.

The city of Nanjing had tested more than 5 million of its 9.3 million residents as of Thursday. Some staff members at the airport, mainly cleaning and ground service workers, tested positive for the virus on Tuesday.

Yang Yi, director of Zhongda Hospital's intensive care department, said that none of the people with confirmed infections were severe cases.

"National, provincial and city medical experts have been asked to treat the patients," she said at a news conference on Thursday. "Specific treatment plans have been made for each patient."

However, she said that except for one teenager, all the confirmed cases were people who had been vaccinated.

"Vaccination still works to lessen the symptoms and shorten the treatment," Yang said. "Local residents should avoid public places, wear masks and maintain social distance to contain the virus."