False-positive nucleic acid test results refers to the actual negative but the results incorrectly shown as positive, leading to this phenomenon is mainly due to laboratory reasons, such as sample contamination, test operation contamination, PCR amplification product contamination, aerosol contamination and so on.
1. Sample contamination: such as in the collection of samples when the container is contaminated, or containers are not tightly closed, resulting in the leakage of viruses and cross-contamination.
2. Operation contamination during testing: During the centrifugation process of nucleic acid testing, due to the excessive speed of the centrifuge, the test samples may be opened and splashed, causing other samples or environmental pollution. In addition, in the process of nucleic acid extraction, improper operation may also lead to mutual contamination between samples, resulting in false-positive results.
3. PCR amplification product contamination: this is the most common contamination phenomenon, PCR amplification product copy amount reaches a certain level, even if a small amount of PCR product is contaminated, there may be false-positive results.
4. Aerosol contamination: In the centrifuge centrifugation process, such as the experimenter repeatedly take samples and open the lid may lead to aerosol contamination.
False positives need to be carefully analyzed and improved.