Second, it may be that the location has become a low-risk area, and before that, you didn't carry out unified nucleic acid testing or other medical observation methods according to official requirements to confirm whether you were infected, and the system automatically identified you as an uncertain factor, so the health code was abnormal; In this case, it is recommended to go to the hospital for nucleic acid testing immediately to confirm the health status. If the nucleic acid test is negative, the health code can return to normal.
Data expansion
nucleic acid testing
Nucleic acid refers to the DNA of a virus. Novel coronavirus nucleic acid was detected in sputum, lower respiratory secretions, blood, feces and urine by RT-PCR or NGS. The specific detection process is as follows:
1. To collect secretions, it is necessary to collect the nasal swab or throat swab of the patient and wipe the nasal cavity or posterior pharyngeal wall and bilateral pharyngeal tonsils.
2. Sample retention: The patient needs to retain the sample, put the swab head into the cell preservation solution, and tighten the tube cover immediately after the tail is cut off.
3. Keep it for inspection. Store the sample tube in a sealed bag for storage and timely inspection.
4. Extraction: Send the sample to the laboratory for nucleic acid extraction, perform fluorescence PCR amplification reaction on the extract, and finally see the results.
If the nucleic acid test is negative, novel coronavirus can't be ruled out, and the factors that may produce false negatives need to be ruled out, including poor sample quality, too early or too late collection process, improper sample storage, transportation and processing, and the reasons for the existence of the technology itself, such as virus variation and PCR inhibition.