China will begin using COVID-19 antigen tests as a supplementary method to improve its early detection capability, the National Health Commission said in a notice on Friday.

Compared to nucleic acid testing — the dominant tool widely deployed in the country's mass testing campaigns, antigen tests give results more quickly but are generally less accurate.

The use of rapid, at home antigen tests is widespread in some countries, but they are much less common in China as only nucleic acid test results are considered the gold standard.

The commission said the inclusion of antigen tests in its tool kit is aimed at upgrading its testing strategy in face of demands arising from the changing virus control situation.

"Confirming the infection of coronavirus still requires a nucleic acid test result. Antigen testing can be used as an additional measure to screen target groups and improve our capability to detect new infections swiftly," the commission said in a statement explaining the notice.

Three categories of people will be able to take an antigen test, according to the commission.

They are people who visit grassroots medical facilities after feeling suspicious respiratory symptoms or having a fever within five days; people undergoing centralized or home isolation; and residents in need of such tests due to personal reasons.

In any circumstances, people who test positive for antigen tests will be managed as COVID-19 cases. They will be required to undergo centralized quarantine and take multiple nucleic acid tests.

Antigen tests will be available in retail drugstores and online shops, it added.