The Food and Drug Administration has advised clinical lab staff and health care providers that coronavirus antigen tests aren’t foolproof and can produce false positives.
The agency stated false positives will occur when users do not follow the instructions for using antigen tests for rapid detection of the virus, CNN reported.
“The FDA is aware of reports of false positive results associated with antigen tests used in nursing homes and other settings and continues to monitor and evaluate these reports and other available information about device safety and performance,” the agency said, CNN reported.
Antigen tests lack the accuracy of molecular polymerase chain reaction tests, but they are quicker and are used as a coronavirus screening tool in places such as nursing homes. The FDA said false positives can take place with any laboratory test and labs should expect them when screening large populations with low rates of infection, even when using very accurate tests, CNN reported.
To secure precise reporting, the FDA counsels providers and lab staff to follow Centers for Disease Control and Prevention guidelines when performing tests. The agency also advised providers to take into consideration the potential occurrence of false positives and follow up with molecular tests, CNN reported.