Self-tests are antigen tests that do not have to be performed by trained personnel but are approved for use by laypersons. Antigen tests detect specific components of the virus. They are also called rapid tests or point-of-care (PoC) tests because they provide the result on the spot within 15 to 20 minutes without the need to involve a laboratory. The first self-tests were approved in Germany in early March. At low viral loads, an antigen test can miss an infection.
Ideally, employees and students carry out the self-tests at home in advance of a campus day, so mobility can be avoided in the event of infection. Instructions can be found here.
Due to the statewide testing requirement, students must now take a citizen test at their place of residence. The previous practice of bringing a photo of a self-test taken at home does not meet the new legal requirements. For this reason, TU Dortmund University will no longer hold self-tests for students from mid-June.
If the self-tests are conducted at home, infected individuals will be prevented from traveling to campus and having contact with other individuals.
To ensure that self-tests are as sensitive as possible and miss as few infected individuals as possible, product development accepts that in rare cases they will give a false positive result. If self-tests are used on a very large scale, then this occurs on a significant scale: For example, if the reliability is 99.5%, there will be an average of five false positive results per 1,000 tests. A PCR test can be used to check whether the result was true positive (infected) or false positive (non-infected). Anyone who obtains a positive result in a self-test is obliged to undergo a PCR test immediately at a test center or at the family doctor's office for control.
Self-tests have the advantage that you can do them at home and get the result immediately. This means that positive cases can be detected before you come in contact with others. However, they are less sensitive than PCR tests. For example, if the viral load is low, they may miss an infection, especially in the pre-symptomatic phase. Because PCR tests are much more sensitive, their predictive power is higher. They are also more likely to detect new mutants. Therefore, anyone who is regularly present on campus should take a PCR test at least once a week after a negative self-test. This procedure also enables TU Dortmund University to check how reliable the self-tests are. The following link provides a chart that illustrates the advantages of combining both testing methods.
Employees of the TU Dortmund receive self-tests from Siemens, which are provided by the state of NRW.