The biggest advantage of antigen detection is easy to operate, fast results, it is the biggest role in the prevention and control of epidemics, is to improve the "early detection" ability. The prevention and control of infectious diseases, early detection is the core element, only as soon as possible to find infected people, in order to control the spread of a smaller range, is conducive to the prevention and control of social epidemics; from the point of view of personal health, "early detection" is also conducive to the early treatment, so that the patient can be prioritized to obtain medical resources as soon as possible. Therefore, the new national guideline puts antigen detection as an important supplement to nucleic acid testing.
Second, antigen test kits are accurate
According to experts from the National Health Commission, the sensitivity of antigen test reagents that have been approved in our country is between 75% and 98%, and the specificity is between 95% and 99%. The accuracy of antigen detection is high, but the sensitivity is not enough. Because the nucleic acid test has an amplification process, so it is more sensitive, while the antigen test does not have an amplification process, relatively speaking, the sensitivity is not enough, so it can not replace the nucleic acid test, but only as a complementary means.
The sensitivity corresponds to the probability of "no missed detection", with the nucleic acid test results as a reference standard, if the antigen test can detect 97 positive results in 100 positive results, the sensitivity of this antigen test product is 97%; specificity corresponds to the "no misdiagnosis" probability, the same against the antigen test, the antigen test can detect 97 positive results in 100 positive results. The specificity corresponds to the probability of "no misdiagnosis", also against the nucleic acid test standard, if 3 out of 100 positive results detected by the antigen test are false positives, then its specificity is 97%.
The main problem that antigen self-testing solves is improving "early detection" of people at risk of infection. Antigen detection is conducive to rapid screening of people at higher risk of infection, facilitating the prevention and control of social epidemics; "early detection" is also conducive to the early isolation of individuals, early treatment, so that the patient as soon as possible to obtain medical resources.