Abnormal nucleic acid mix-up indicates false positives, false negatives, positives, and specimen failure, and another nucleic acid test is recommended. 1. False Positive: Abnormal nucleic acid mix-ups may result in false positive results. A false positive result indicates that the subject is not infected with the virus, but the nucleic acid test is positive, usually caused by cross-contamination between samples or nucleic acid contamination in the laboratory. 2. False Negative: An abnormal nucleic acid mix-up may result in a false negative result. Generally, this means that the subject’s clinical symptoms and epidemiologic history support a positive result, but the viral nucleic acid test result is negative, and the test result is inconsistent with the clinical result. 3. Positive: Nucleic acid mixing refers to the swabbing of samples from more than one person, placed in the same sampling tube at the same time, and sent for testing together. If the mixed test is abnormal, some of the samples may be positive. In this case, it is recommended that a new single tube swab be collected and reviewed 1 to 1 to determine which one is positive. 4. Specimen Failure: Abnormal nucleic acid mix-ups may be caused by specimen failure, which is often the result of too many tests or a hostile environment. If the sample is not collected and tested as soon as possible, the sample will degrade and become untestable, at which point it will need to be recollected. If a person has an abnormal result after a mixed nucleic acid test, he or she should have the nucleic acid test reviewed in a hospital and follow the doctor’s instructions.