Why does the nucleic acid test in Shanghai’s sealed area need to be tested once a day?

Some netizens asked, why does nucleic acid testing in the Shanghai containment area need to be done once a day? Is this necessary? According to experts, nucleic acid testing is done once a day because there is currently a pattern of disease occurrence and development and detection technology. Let’s find out the specific reasons quickly.

Why should nucleic acid testing be performed once a day in the Shanghai containment area? Judging from the course of the new coronavirus infection, there is a certain incubation period. When the viral load in the human body is low, or the virus content in the specimen is low, it has not yet When the detection limit of the detection reagent is reached, the test result may be negative at this time. When the virus continues to grow and replicate in the body, or the virus content in the specimen is high and reaches or exceeds the detection limit of the detection reagent, the test result is positive. Of course, the incubation period varies among individuals and is closely related to individual immunity; the virus content in different specimens varies and is affected by sampling and detection technology. When the community completes a round of nucleic acid screening, usually those infected with higher viral loads can be screened, but some infected people with lower viral loads will show negative nucleic acid results. If the latter cannot be detected in time, as the virus continues to multiply and grow in the body, it will develop into a contagious infected person and continue to spread the virus in the community. Therefore, it is necessary to dynamically detect positive infected persons as early as possible through multiple consecutive nucleic acid screenings, and achieve dynamic clearing of society as soon as possible.

The latest epidemic situation in Shanghai from 0 to 24:00 on April 19, 2022, there were 2,494 new local confirmed cases of new coronavirus pneumonia and 16,407 asymptomatic infections, of which 533 confirmed cases were previously asymptomatic infections. As a result, 1,800 confirmed cases and 16,178 asymptomatic infections were discovered during isolation control, and the rest were discovered during the investigation of relevant risk groups.