Two antigen tests for rapid diagnosis of COVID-19, which detect the presence of SARS-CoV-2 virus proteins within 15 minutes after testing, show very promising initial results. In the coming weeks, several important studies and evaluations will be completed at various test lanes in the Netherlands. The aspects being researched include the reliability of the test and the applicability of the test in the Netherlands as a supplement to the polymerase chain reaction (PCR) tests.
The antigen test is a test that detects the presence of certain viral proteins from the novel coronavirus in nasal and pharyngeal mucus. The test yields a result fifteen minutes after testing. Laboratories, hospitals, Municipal Public Health Services (GGDs) and RIVM are working closely on this research to gather information and see how this type of test can be used in practice, in addition to and partly as a replacement for the current PCR tests. Although the initial research results in the test lanes are promising, the evaluations are not yet completed. The test must also be examined in situations other than the test lanes. It is important to prepare thoroughly before starting to use the tests in actual practice.
Using the tests in practice
Meanwhile, a working group consisting of experts from the reference laboratories, GGDs, hospitals, and RIVM is working to determine the groups for which the antigen tests offer the most added value. There are also challenges in terms of logistics. Although the test does yield a rapid diagnostic result, it takes considerably more time to deploy and read than required for the analysis of a PCR test. An analyst in a laboratory can analyse about 600 tests per day for the PCR test currently used most widely. The same analyst could analyse about 60 antigen tests per day. This will have consequences for staffing capacity requirements.
Reliability
The antigen test does not detect all infections. A positive test result indicates that a person has the virus, and usually in such quantities that the person is contagious at that time. The test is sensitive enough to perform well in that respect. However, if the test result is negative, the test may have failed to detect infections in people who do in fact have the virus, but are not yet contagious. Depending on the reasons why someone has been tested, it could for example be decided to repeat the test after a few days. It is important to pay attention to this in the communication with the people who are tested.
Field research
Various studies on the rapid antigen test will take place in the near future. In the upcoming week, RIVM will investigate how the test works in cooperation with GGD Haaglanden and GGD Rotterdam-Rijnmond, among others. RIVM analysts will perform the analyses of the antigen tests at various locations in mobile laboratories of the RIVM Environmental Incident Service. At the test lanes where the rapid antigen tests are being researched, people who come for a test will be asked if they would like to participate in the rapid test in addition to the standard PCR test.
Basic rules remain important
If the test is deployed in actual practice, it will still be important for people to follow the basic rules: keep your distance, wash your hands, and stay home and get tested if you have symptoms.