Shanghai on Monday finished collecting samples for nucleic acid testing from over 24 million residents as part of the city's latest effort to cut off COVID-19 transmission in communities and contain the resurgence of the virus, local authorities said on Monday night.

"With the active cooperation of the local residents, the city finished the latest round of nucleic acid sampling work on April 4," the office of the Shanghai municipal leading group for COVID-19 prevention and control said in a statement.

Shanghai conducted citywide nucleic acid testing on Monday after mass antigen testing on Sunday. The city has been placed under temporary closed-off management after the rate of COVID-19 infections surged in recent days.

Further work, including testing, multiple checks, the transportation of positive cases, and the analysis and assessment of the COVID-19 situation, will be carried out in an orderly manner, according to the statement.

After all the work is completed, follow-up control measures will be implemented based on relevant national regulations and the results of the mass screening.

More than 38,000 medics from 15 provincial-level regions across China have rushed to Shanghai to aid in the battle against the COVID-19 epidemic, according to the National Health Commission (NHC).

Some 27,000 medics are responsible for sampling and testing work, and another 11,000 are working in temporary hospitals, according to Jiao Yahui, a senior NHC official.

Shanghai reported 268 local transmissions of COVID-19 and 13,086 asymptomatic cases on Monday, local authorities said on Tuesday morning. 

As of 9 a.m. on Monday, more than 92,000 close contacts and over 111,000 secondary close contacts had been placed under medical observation in the latest resurgence, according to a press conference held by the Shanghai Municipal Health Commission.

The commission noted that children who test positive can stay with their parents who also test positive in children's wards, and be treated simultaneously. Pediatric facilities are in place to ensure the professional treatment and care of all children who test positive in the city, it added.

Read more:

Bus drivers volunteer to deliver vegetables to residences in Shanghai

Thousands of medics nationwide rush to aid Shanghai in COVID-19 response

(With input from Xinhua)