Because there is still no vaccine or therapy for SARS-CoV-2, tests play an important role in controlling its spread. However, they currently take a relatively long time. Prof. Dr Christian Kaltschmidt and other researchers have tested a method that works much faster. Photo: Marcel Mompour

The most common procedure for testing whether someone has become infected with SARS-CoV-2 is a so-called PCR test. These use the genetic material of the virus as a basis. This is also what the Bielefeld scientists did in their study. PCR tests always follow a similar pattern. First, genetic material is needed from a test person. This is usually obtained by a smear test in the mouth, nose, or throat. ‘If a person is infected with SARS-CoV-2, the sample will also contain genetic material from the virus in the form of what is called RNA,’ said Kaltschmidt. The RNA molecules are isolated in a chemical process. However, the sample does not contain enough RNA for a test to detect it immediately. Therefore, it has to be amplified. 

The Bielefeld researchers used a special thermal cycler—the NEXTGENPCR—for their process. Thanks to the special design including several temperature zones, reactions in the device run particularly effectively and fully automatically. ‘We have oriented the procedure towards the so-called Drosten protocol of the Berlin Charité and the protocol of the Center of Disease Control and Prevention in Atlanta,’ says Kaltschmidt. These are standards for SARS-CoV-2 tests. Using their method, the researchers were able to repeat the results of conventional PCR tests—only in a much shorter time and with less effort.

Whether a person is infected with SARS-CoV-2 can be detected in tests. The genetic material is multiplied in a thermal cycler. The thermal cycler used in the new study (see photo) enables around 570 analyses per hour. Photo: Bielefeld University/M.-D. Müller

Kaltschmidt sees many advantages in the new process. For example, such a test could be used especially where rapid results are required. ‘When cruise ships resume operations, for example, they could test each person in a short time before they board the ship.’

Other participants in the study were the Heart and Diabetes Center NRW in Bad Oeynhausen, the molecular neurobiology research group at Bielefeld University, the Evangelisches Klinikum Bethel, and the Forschungsverbund Biomedizin Bielefeld OWL e.V.