According to the News of China Daily WeChat Public Account on March 12, the State Food and Drug Administration issued a notice approving the application change of the self-test application of new crown antigen products in Nanjing Novizan, Beijing Jinwolf, Shenzhen Huada Inyuan, Guangzhou Wanfu Biologics, and Beijing Huaketai Biologics.
Since then, five new crown antigen self-test products have been officially launched.
Residents can purchase reagents for self-testing! Covid-19 testing strategy adjustments
In order to further optimize the detection strategy of the new crown virus, according to the needs of epidemic prevention and control, the comprehensive group of the joint prevention and control mechanism of the State Council decided to promote the monitoring mode of "antigen screening and nucleic acid diagnosis", and add antigen detection as a supplement to nucleic acid detection. Recently, the comprehensive group of the mechanism formulated and issued the "Application Plan for the Detection of New Coronavirus Antigens (Trial)" (hereinafter referred to as the "Plan"), requiring all localities to seriously organize the implementation.
The "Plan" stipulates the applicable groups for antigen testing: first, 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; second, isolation and observation personnel, including home isolation observation, close contact and sub-close connection, entry isolation observation, sealing and control area and control area; third, community residents with antigen self-testing needs.
The "Plan" makes it clear that if community residents have self-testing needs, they can purchase antigen detection reagents for self-testing through retail pharmacies, online sales platforms and other channels. It should be noted that in order to ensure the quality of sampling and testing, residents need to carefully read the instructions and standardize the operations such as sampling, sampling, and result interpretation in accordance with the prescribed requirements and procedures.
When the antigen test is positive, regardless of whether there are respiratory tract, fever and other symptoms, residents should immediately report to their community (village and town), and the community (village) contact the emergency center to transfer residents to a medical institution that has set up a fever clinic for nucleic acid testing in accordance with the guidelines for the transfer of personnel related to the new crown pneumonia epidemic. After the positive person uses the sampling swab, sampling tube, test card, etc., into a sealed bag and transported to the medical institution for medical waste disposal.
What exactly is antigen testing? What is the difference from nucleic acid testing?
Zhang Wenhong, head of the Shanghai New Crown Pneumonia Clinical Treatment Expert Group and director of the Department of Infectious Diseases of Huashan Hospital affiliated to Fudan University, pointed out in an interview with the media that antigens are like "clothes" worn outside the virus, and nucleic acid is the gene inside the virus.
These two tests are slightly different, the detection method of antigens is to measure the "clothes" from the antibody, after the comprehensive specificity, the virus can be displayed; and the nucleic acid detection is more complex and needs to be completed by amplification, because with the amplification link, the sensitivity of nucleic acid detection will be higher, but the corresponding results will take longer.
Zhang Wenhong said that in the first stage of our fight against the epidemic in China, we have achieved "clearance" through rapid combat through nucleic acid testing, but recently we have also found that after the Omilon variant came out, the overall speed of virus transmission was accelerating, not only in Shanghai, but also in other parts of the country, there were more patients in different regions, and the speed of virus transmission in a short period of time was very fast.
"At this time, we will find that if the detection speed only relies on nucleic acids, there will be certain difficulties." Zhang Wenhong said that because nucleic acids need to borrow machines, and the sampling requirements, machine amplification have a very professional set of systems, if this place is inconvenient to sample or there are no suitable conditions to do amplification, is there a simpler way?
He said that just like the home pregnancy test stick to detect whether pregnant is pregnant, antigen testing can be tested at home, and it is very fast, and it can also be detected in hospitals with poor conditions, and the cost is relatively low.
Zhang Wenhong explained that everything has its two sides, and the antigen test is slightly less sensitive because it does not amplify, but once it is positive, it will have strong value. Antigen testing has been adopted in the fight against the epidemic in Hong Kong, and the institutions involved in the fight against the epidemic have also recognized this testing method, and through the antigen test, they can directly declare whether they are infected with the new crown, and then take a series of measures.
