What does antigen testing mean? What is the difference between antigen testing and nucleic acid testing?

In the case of many outbreaks in China, antigen detection was developed by Professor Huang Ailong of Chongqing Medical University, and single-copy field detection can be realized without any additional instruments and equipment. What does antigen testing mean? What's the difference between it and nucleic acid detection?

1, what is antigen detection antigen is like a "dress" worn outside the virus, and nucleic acid is the gene inside the virus. Antigen detection is to detect the "clothing" part from the antibody, so that the virus can be displayed.

2. What's the difference? Antigen detection is more convenient and quick, but the sensitivity is slightly poor.

Nucleic acid detection is more complicated and takes a long time to get results, but it is more sensitive.

Can antigen test results replace nucleic acid test results?

I can't.

Nucleic acid detection is still the basis of diagnosing COVID-19 infection.

* antigen detection can be used as a supplement to nucleic acid detection.

① Nucleic acid positive test: Take corresponding measures according to patients infected in COVID-19 or diagnosed in COVID-19.

② The nucleic acid test was negative, but the antigen test was positive: it was regarded as COVID-19 infected person. Take measures such as centralized isolation, close observation and continuous nucleic acid detection.

③ The original test was positive: the diagnosis must be confirmed by nucleic acid test immediately.

3, antigen self-test self-test step antigen self-test preparation

1. Wash your hands

Wash your hands with running water or hand disinfectant.

(2), understand the detection process

Carefully read the matching instructions of antigen self-test reagents and the precautions related to antigen self-test.

③ Preparation of reagents

Check whether the antigen self-test reagent is within the warranty period, and check whether the contents such as nasal swab, sampling tube and test card are missing or damaged.

* If the reagent expires or the contents of the reagent are lost or damaged, the detection reagent should be replaced in time.

④ Confirm the test environment.

Colloidal gold test paper generally requires room temperature of 14℃-30℃ to avoid abnormal test results caused by supercooling, overheating or excessive humidity. The antigen test card is unpacked and placed in a flat and clean place.

Sample collection

Wipe your nose with toilet paper.

Carefully open the outer package of the nasal swab to avoid hand contact with the swab head.

Tilt your head slightly, hold the tail of a cotton swab in one hand and stick it on one nostril, then slowly seep back to 1- 1.5 cm along the bottom of the inferior nasal passage and stick it on the nasal cavity for at least 4 times (the residence time is not less than 15 seconds), and then repeat the same operation on the other nasal cavity with the same cotton swab.

*/kloc-people over 0/4 years old can take nasal swab samples by themselves.

* Self-taught students aged 2-14 should be sampled by other adults.

Antigen test

Immediately after collecting the sample, put the nasal swab into the sampling tube, rotate the swab head in the preservation solution for at least 30 seconds, and squeeze the swab head through the outer wall of the sampling tube for at least 5 times by hand.

Squeeze the liquid from the swab head through the outer wall of the sampling tube by hand, and then discard the swab. After covering the sampling tube, drop the liquid vertically into the sample hole of the detection card.

According to the reagent instructions, please wait a while before interpreting the results.

Results viewing

The positive result indicated that novel coronavirus antigen was detected in the sample, and novel coronavirus infection was suspected. Please report immediately and seek medical treatment in isolation according to the prevention and control regulations.

The negative results showed that novel coronavirus antigen was not detected in the sample, but the negative results could not completely rule out the possibility of infection. Follow-up treatment should be carried out according to the local epidemic prevention and control policies, and it is recommended to go to the hospital for further examination if necessary.