Are there any limitations to COVID-19 diagnostic tests?

With any diagnostic test, there is the potential for false negatives or false positives. For existing COVID-19 tests in the U.S., there have been reports of false negative tests. False negative tests can occur if a specimen was not properly obtained or if a patient was tested too early or too late in their infection. Laboratory error is also a possible cause of false negative test results. Conversely, false positive reports are less common.