How is the test carried out?
In most cases, the test involves taking a throat swab or a throat-nose swab from the patient. The Robert Koch Institute also recommends that, in the case of a well-founded suspicion, samples should not only be taken from the upper airways but also from the lower airways, for example from coughing up secretions from the bronchi or lungs.
What happens with the samples?
The samples are tested for coronavirus in diagnostic laboratories. The procedure is based on a so-called polymerase chain reaction (PCR). Such tests take about five hours and have become standard procedures in laboratories. They are also used to clarify hereditary diseases or to determine paternity.
In PCR, a specifically selected piece of DNA is copied and multiplied in a thermocycler in order to search for specific DNA pieces, such as coronavirus. The method then shows whether and how many pathogens are present in the body. In viral infections, this is called the "viral load."
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How does testing for the coronavirus work? | DW | 04.03.2020