Beijing is also going to conduct coronavirus antigen testing? Who needs the test?

On May 11, Beijing held the 331st COVID-19 epidemic prevention and control press conference. According to the report, Beijing has carried out COVID-19 antigen testing for personnel in key areas and key industries.

After hearing the news, netizens in Beijing were confused: What is antigen testing? Who needs to be tested? When should it be tested? How should it be tested? Netizens in Shanghai sent their experiences.

01

What is antigen testing? How is it different from nucleic acid testing?

Nucleic acid testing: Using PCR (polymerase chain reaction) testing technology, a section of the RNA fragment of the new coronavirus is first reverse transcribed into double-stranded DNA, and then amplified by DNA polymerase to continuously amplify the viral gene fragment. Its biggest feature is that it can greatly increase trace amounts of nucleic acid in vitro, but it will take longer to obtain the results accordingly.

Antigen detection: uses specific antibodies to identify and bind to a target antigen. Most of the approved antigen detection products use the SARS-CoV-2 N protein as the target for antigen detection. It is more convenient and faster, but has slightly lower sensitivity.

02

Why use antigen testing?

"After the emergence of Omicron (new variant of the novel coronavirus), the spread of the virus has accelerated. If our testing still relies entirely on nucleic acid as it did in the beginning, we will have certain difficulties." Zhang Wenhong, leader of the Shanghai COVID-19 Clinical Treatment Experts Group and director of the Infectious Diseases Department of Huashan Hospital affiliated to Fudan University, once explained, "Because nucleic acid requires the use of machines, and the sampling requirements and the expansion of the machines require professional operation, on-site sampling also has certain inconveniences." In contrast, "antigen testing is very convenient. You can test it at home by yourself, and the cost is relatively low. Because it does not involve gene amplification, its sensitivity is slightly lower, but once it detects a positive result, it will have very strong value."

03

Can antigen testing replace nucleic acid testing?

At present, nucleic acid testing is still the basis for confirming new coronavirus infection. Antigen testing is fast and simple. It is used as a supplementary means to screen specific populations, which is conducive to improving the "early detection" capability, but it cannot replace nucleic acid testing.

04

Who needs testing in Beijing?

People in key areas: People in the closed and controlled areas

Personnel in key industries: express delivery workers, workers in imported non-cold chain goods, workers in farmers' markets and wholesale markets, workers in catering units, supermarkets and other food business units, food delivery workers, hotel workers, taxi drivers (including online car-hailing), bus and subway staff, decoration, loading and unloading, and transportation workers, medical institution staff, sanitation workers, property, cleaning, and security workers, public security, urban management law enforcement, market supervision and other front-line personnel.

Key risk persons: persons with positive nucleic acid mixed tube test results, high-risk persons, and persons whose Beijing Health Code “pop-up window” appears.

05

When is the test?

People in key areas: Conduct nucleic acid tests once a day on the 1st, 2nd, 3rd, 4th, 7th and 10th days after the lockdown, and conduct antigen tests once a day on the 5th and 6th days.

Key industry personnel: During the local epidemic, in principle, antigen testing should be conducted once a day on the days between nucleic acid tests currently required. Among them, nucleic acid and antigen testing requirements for food delivery workers shall be implemented in accordance with the food delivery personnel prevention and control guidelines issued by the municipal commerce department.

Key risk personnel: After the 1:5, 1:10, and 1:20 mixed tube positive results appear, an antigen test will be conducted at the same time as the nucleic acid re-examination; for high-risk personnel and those who have the Beijing Health Code "pop-up window", on the basis of nucleic acid testing as required, an antigen test will be conducted once a day on the days between nucleic acid tests.

06

Who should I ask for testing?

Personnel in key areas: Each district will organize streets (townships), communities (villages) to implement it, and test kits will be distributed uniformly on the first day of the implementation of lockdown and control.

Personnel in key industries: coordinated by the competent departments of the industry and implemented by the local authorities; antigen testing for personnel with mixed positive nucleic acid tests shall be organized and implemented by the district or unit that organizes the testing.

Key risk persons: The local community (village) will supervise the relevant personnel to implement it.

07

How to use antigen test reagents? Click the link below

https://v.qq.com/x/page/z3327tyhw9a.html

Result interpretation:

Positive result: Bands appear at both "C" and "T", and the color of the bands may be dark or light;

Negative result: a band appears at "C", but not at "T";

Invalid result: Regardless of whether a band is displayed at "T", a band is displayed at "C".

08

How to deal with detection anomalies?

Wu Fan, a member of the expert group of the Shanghai Epidemic Prevention and Control Leading Group and vice president of the Shanghai Medical College of Fudan University, reminded that for those with abnormal nucleic acid screening, citizens need to do the following five steps after receiving the notification:

"Quiet": Stay calm and don't panic.

"Isolate": Immediately self-isolate on the spot. If conditions permit, stay in a single room, wear a mask, keep a certain distance from others, and keep communication open.

"Think": Carefully review your recent activities.

"Notify": Inform people who have had close contact with you recently to stay home immediately, avoid going to crowded places, monitor your own health, and cooperate with epidemic investigation and control work.

"Preparation": Pack the items you need to go to a medical institution or centralized isolation and treatment point, such as an ID card, common medicines, spare clothes, daily necessities, etc. We especially remind everyone to bring your mobile phone charging cable.

After completing these five steps, you can patiently wait for further notifications from relevant departments and subsequent transfers. For those who test positive for mixed sampling, citizens will inform their location information after receiving the notification, and immediately stay in place, wear masks, keep a certain distance from others, and wait for the sampling personnel to conduct nucleic acid re-examination.

Compiled from: Guangming.com, Beijing Daily, CCTV.com, China Business News, People's Daily

Content from: Popular Science Health Education Center