A revised edition of a guideline designed to help improve the organization and implementation of mass nucleic acid testing was published by the National Health Commission on Sept 13.

It was revised to more effectively respond to potential and recent outbreaks caused by the Delta variant of coronavirus.

Cities with less than 5 million residents should complete nucleic acid testing for every individual within 2 days, while ones with more than 5 million are expected to complete the task within 3 days, the guideline read.

When necessary, cities can also apply for provincial-level and even nationwide support to ensure testing is completed on schedule.

When the source of infection is unknown, at least three rounds of mass nucleic acid testing should be conducted.

Testing frequency afterward will be determined based on the results of epidemiological investigation, identification of the virus, previous testing and the size of affected area.

Each provincial-level region should also have at least 10 nucleic acid testing support teams on standby at all times, the guideline outlined.

Depending on the population of a city, two to five labs or places that can be converted to labs should be secured, which should be able to accommodate five nucleic acid testing support teams and store necessary equipment, reagents, consumables and items for disinfection.