On April 13, 2020, the Centers for Disease Control and Prevention (CDC) issued guidance to occupational health programs and public health officials making decisions about return-to-work protocols for healthcare personnel (HCP) with confirmed or suspected COVID-19. This guidance provides that a “test-based” strategy for return-to-work protocols is the preferred method for determining when HCP may safely return to work. This test-based strategy is contrasted with a more general “non-test-based” strategy that relies on monitoring the HCP for a lack of symptoms, including fever. While at this point the CDC’s test-based strategy relies exclusively on nucleic acid testing, several types of testing such as antibody (serologic) and antigen testing are becoming more available and accessible. Given these various testing options, health facilities must consider the practical and legal implications of each type of test when implementing an HCP testing plan.

Q: Are nucleic acid tests accurate?

A: Nucleic acid tests or nucleic acid amplification tests (NAAT) are the molecular tests that detect the virus’s genetic material (RNA) in a sample from a patient’s respiratory system, typically via a nasal swab. A positive test result indicates that an individual is currently infected with SARS-CoV-2, the virus that causes COVID-19. According to the Food and Drug Administration (FDA), FDA-authorized nucleic acid tests for SARS-CoV-2 meet the Emergency Use Authorization statutory standard and are believed to be highly accurate.

Q: What are the advantages and disadvantages of using nucleic acid tests?

A: As has been widely discussed over the past few months, nucleic acid tests require not only lab testing capacity but also availability of all of the components of testing, such as swabs and reagents, as well as PPE for individuals collecting the samples. Additionally, although these tests are believed to be highly accurate, the sensitivity of these tests varies depending on both the timing and the way the sample is collected. While some nucleic acid tests are point-of-care tests, meaning results may be available at the testing site in less than an hour, other tests must be sent to a laboratory to analyze, a process that takes several days for test results to be reported. See https://www.cdc.gov/coronavirus/2019-ncov/testing/diagnostic-testing.html. Certainly, a nucleic acid test is preferred if the goal is to determine whether an individual is currently infected with the virus and thus likely to be contagious.

Q: What are antibody tests?

A: Antibody tests are blood tests that check for the presence of antibodies. If an individual has antibodies, that person was previously infected with the virus. However, depending on when someone was infected and the timing of the test, the test may not detect antibodies in someone with a current COVID-19 diagnosis. According to the CDC, antibody tests should not be used as the only way to diagnose someone as being currently infected.

Q: What are the advantages and disadvantages of using antibody tests?

A: While antibody testing may seem promising for determining which individuals are “safe” to return to work, the presence of antibodies has not been determined to provide immunity to COVID-19. Additionally, because of the novelty of this virus, research is still being conducted as to whether detectable antibodies may decline or even disappear over time. Studies, including recent data awaiting peer review from UC San Francisco and UC Berkeley, are analyzing the accuracy of more than 120 available antibody tests. Given this uncertainty regarding the various antibody tests on the market, health facilities should proceed with caution, checking the validation data provided by the manufacturer before utilizing these tests.

Q: What do we know about antigen tests?

A: Like the nucleic acid tests, antigen testing would confirm that an individual has an active infection. Instead of looking for the virus’s actual genetic material, the antigen test looks for the presence of the virus’s outer protein. Antigen tests can identify viruses in nasal and oropharyngeal secretion. To date, there are no authorized COVID-19 antigen tests on the market. However, as expected, several companies are developing them and seeking FDA approval.

Q: What are the advantages and disadvantages of using antigen tests?

A: Preliminary reviews of antigen tests indicate that they could provide rapid results – in a matter of minutes – even at home. As a result, these tests could be used to screen people in health facilities where it’s important to find out quickly if an individual is currently infected. However, until the efficacy of these tests is established, health facilities would still need to augment the antigen test with a nucleic acid test to confirm a COVID-19 diagnosis.

Q: What should health facilities do about testing?

A: Every health facility wants to reassure its staff as well as its patients that everything is being done to ensure a safe environment and minimize the risk of COVID-19. A rational testing program for all HCP, including those returning to work after infection, is a key part of this process. Given the rapid proliferation of different types of tests, health facilities have an obligation to ensure they are employing appropriate testing protocols.

After evaluating the available scientific data, health facilities should carefully consider the type of HCP testing they will utilize. The risks and benefits of various tests should be weighed, and the reasons to use a certain test or tests should be documented. Such documentation will go a long way toward protecting against the expected increase in COVID-19-related patient liability claims as well as workers’ compensation claims by HCP.