China has granted approval to five COVID-19 antigen test kits made by local companies to be used for self-testing as a way to beef up early detection capabilities to cope with the more evasive and transmissible Omicron variant.

In two separate notices, issued on Friday and Saturday, the National Medical Products Administration allowed five companies－Beijing Savant Biotechnology, Nanjing Vazyme Biotech, Guangzhou Wondfo Biotech, Beijing Jinwofu Bioengineering Technology and Shenzhen-based BGI PathoGenesis Pharmaceutical Technology－to revise its COVID-19 antigen test kit's certificate to allow self-test use.

The approvals come after the State Council joint prevention and control mechanism against COVID-19 said on Friday that it would allow the public to buy COVID-19 antigen self-test kits in stores and online.

The COVID-19 antigen test is a supplementary diagnostic method to the mainstream nucleic acid testing to improve early detection capability, according to a notice published on the National Health Commission's website.

The antigen test kits can be used by people who have had fever or respiratory symptoms within five days, by people who are under quarantine and other residents who simply want to take a test, the notice said.

People who test positive with COVID-19 antigen kits should immediately contact local authorities regardless of whether or not they show symptoms, it said.

A nucleic acid test result is still needed to confirm novel coronavirus infection. People who test positive with an antigen test but negative with a nucleic acid test should undergo quarantine, close observation and repeated nucleic acid testing, the notice added.

LBX Pharmacy said in a WeChat post on Saturday that the first shipments of COVID-19 antigen test kits will be available at its stores in 12 provincial-level regions within days and that the kits can show test results within 15 minutes.

Cowell Pharmacy said the antigen test kits will be available at its stores in Henan, Jiangxi and Liaoning provinces and its online store on WeChat soon.

Zhang Wenhong, head of the infectious disease department at Fudan University's Huashan Hospital, said the nucleic acid test is more accurate than COVID-19 antigen tests but it takes longer to get the results.

China has successfully maintained a zero-COVID policy through its rapid mass nucleic acid tests, but the Omicron variant is more transmissible and requires faster testing, he told Paper.cn.

Nucleic acid tests require sophisticated machines and professional personnel, while the antigen test can be done at home or in ordinary hospitals, he said.

But the antigen test is less sensitive than the nucleic acid test, he said, and at the early stage of the infection the antigen test might not be able to detect infection due to a low amount of the novel coronaviruses in the body, he said.

Many COVID-19 patients contracting the Omicron variant are asymptomatic, so the COVID-19 antigen test helps boost testing abilities, and the authorities can quickly identify infected people through home testing to reinforce the zero-COVID policy, he added.