According to the news released on the official website of the National Health and Health Commission on March 11, the Comprehensive Group of the Joint Prevention and Control Mechanism of the State Council in response to the novel coronavirus pneumonia epidemic decided to add antigen detection as a supplement to nucleic acid testing, and organized the formulation of the "New Coronavirus Antigen Detection Application Plan (Trial)" (hereinafter referred to as the "Plan").
The plan will help guide all localities to scientifically and rationally apply the new crown virus antigen test, standardize the disposal management after the antigen test is positive, and further improve the "early detection" capability.
According to the plan, the applicable groups of antigen testing include those who go to primary medical and health institutions for treatment, accompanied by respiratory tract, fever and other symptoms and have symptoms within 5 days; isolation and observation personnel, including home isolation observation, close and sub-close contact, entry isolation observation, sealing and control areas and control areas; and community residents with antigen self-testing needs.
Community residents who have self-testing needs can purchase antigen detection reagents for self-testing through retail pharmacies, online sales platforms and other channels.
In particular, the programme states that nucleic acid testing is the basis for confirming the diagnosis of COVID-19 infection. In the process of nucleic acid test confirmation, if the nucleic acid test is positive, regardless of whether the antigen test result is positive or negative, corresponding measures are taken according to the new crown virus infection or the new crown pneumonia confirmed patient; if the nucleic acid test is negative but the antigen test is positive, it is regarded as the new crown virus infected person to take measures such as centralized isolation, close observation, and continuous nucleic acid testing.
Limited by factors such as manpower and material costs, nucleic acid testing capabilities in some countries and regions cannot meet the needs of epidemic prevention and control. In this case, Europe, the United States, Australia, Singapore, Japan, etc. have begun to take antigen detection as the core of the prevention and control strategy.
Professor Lu Hongzhou, president of the Third People's Hospital of Shenzhen and national clinical research center for infectious diseases, told the first financial reporter: "Compared with nucleic acid testing, antigen detection has the advantages of convenience, speed and low cost, and ordinary people can be very convenient to test at home." With the changes in the mainland's epidemic prevention policy, antigen self-testing will serve as a good supplement to nucleic acid testing. ”
Lu Hongzhou said that although the application of some new technologies in antigen detection reagents has greatly improved the sensitivity of antigen detection, the detection rate of this detection method is still significantly lower than that of nucleic acid detection, usually only strong positive samples can be detected, and there is a certain false negative rate, so some patients with low viral load will be missed, so nucleic acid testing is still the gold standard.
"The specificity of reliable antigen testing reagents is 99%, and the results are credible; however, given that nucleic acid testing is still the gold standard, nucleic acid testing confirmation is still required if the antigen test is positive." Lu Hongzhou told the first financial reporter.
Lu Hongzhou believes that at present, Omilon has begun to expand local transmission on the mainland, and the strategy of antigen detection will become a useful supplement to the nucleic acid-based screening system, and can also reduce the possible exposure risk in the process of nucleic acid sampling to a certain extent. However, due to the sensitivity of antigen detection kits, under the current epidemic prevention policy in the mainland, it is not suitable to use the antigen self-test results as the basis for medical treatment, travel and public places.
At the close of trading on the 11th, the stock prices of Jiuan Medical, Wanfu Biological, Oriental Biology and other new crown antigen reagent manufacturers rose or were close to the limit. Previously, companies such as Jiuan Medical, Icon Bio and Oriental Biotech have also obtained emergency authorization approval from the US FDA.
In November last year, the State Food and Drug Administration issued a medical device approval document (quasi-production) to be collected, and companies such as Wanfu Bio, Jinwolf and Huada Inyuan were listed.
As early as November 2020, the State Drug Administration approved the novel coronavirus antigen detection kit of Guangzhou Wanfu Biologics and Beijing Jinwolf Biologics in an emergency manner. According to the website of the Food and Drug Administration, the two products approved above are the first time that the mainland has approved the new crown virus antigen detection reagent, and the product testing time is within 20 minutes. Rapid detection of positive cases at high viral loads during acute infection can be used for early triage and rapid management of suspected populations.