These tests are failing.
Some antibody tests for the coronavirus have such a high rate of false results that they should be discontinued, a new study review finds.
The tests, which some have mistakenly used to claim immunity from the deadly virus, sample blood to find COVID-19 antibodies, which can confirm whether a person has previously been infected. But test accuracy actually varies wildly based on manufacturer.
In a review of 40 previous studies on COVID-19 antibody test accuracy, researchers found a huge fluctuation in the rate of false positives and negatives based on each test’s method and maker.
Rapid point-of-care tests, which use a method called lateral flow immunoassays (LFIAs), were found to deliver the highest rates of inaccurate results, authors found.
“In summary, we have found major weaknesses in the evidence base for serological tests for COVID-19,” study authors write in the review, published Wednesday in medical journal the BMJ.
The researchers recommend the point-of-care tests be discontinued until they can be improved. “Current evidence does not support the continued use of existing point-of-care tests,” the authors write.
Other non-point-of-care antibody tests were found to be more accurate, but still currently “unreliable,” and “characterized by risks of bias.”
Inaccurate antibody tests pose a threat to public health, the Centers for Disease Control and Prevention maintain, as false positives — which researchers found to be less common than false negatives — can give individuals misplaced confidence that they are immune to the coronavirus.
The CDC has previously admitted to knowing antibody tests may be wrong up to half the time. The agency now maintains a list of faulty and fraudulent antibody tests.