Antigen test and nucleic acid test have different testing principles, different application scenarios and different accuracy.
Nucleic acid test is to collect nasopharyngeal swabs and amplify the samples in vitro. If there is a tendency of amplification after fluorescence quantitative PCR, it means that the body has been infected with the virus and it is positive. If there is no amplification, i.e. the sample does not contain viral genes or fragments of genetic material, it is negative.
The antigen test utilizes test strips with antibodies and unique biochemical reactions. The collected sample is dissolved and dropped into the test strip. If the sample contains antigenic substances, an antigen-antibody reaction occurs, and the test strip shows bands, which is positive and suggests that the organism may be infected.
Antigen test is fast. 15 minutes or so can produce the results, you can test at home, while the nucleic acid test needs to be sampled and tested by hospitals and other professional organizations, so antigen test has a faster and more convenient characteristics, can be detected early, early isolation, early treatment.
Antigen test is a complementary means to nucleic acid test, and cannot replace nucleic acid test. If the antigen test is positive, it should be immediately reported to the community and the CDC department under the jurisdiction, and closed-loop transfer to the fever clinic for re-testing of nucleic acid.