How does the test of COVID-19 work?

How does the test of COVID-19 work?

Smears from the mouth, nose or throat contain the genetic material of the virus in infected people. Almost 50 laboratories in Germany examine these samples. The number could continue to rise. The viral genome is detected using a molecular test – the so-called polymerise chain reaction (real-time RT-PCR). The device reproduces the genetic material in several runs until it is detectable. If it is not detected after 35 cycles, the test is considered negative.

The test method is established and reliable, but care must be taken to do this. Errors in sampling or transportation can lead to incorrect results.

Not all are tested

The doctors in the in-house practice, the clinic and specially set up test centres decide according to the guidelines of the Robert Koch Institute whether the test makes sense. In addition to the symptoms, the person must have been in contact with a confirmed corona case in order to be considered a suspected case.

In Germany, 84,000 tests were carried out per week in the first week of March, after which 160,000 and finally more than 360,000 tests were carried out per week, according to the National Association of Statutory Health Insurance Physicians (KBV). There are also additional capacities, which are, however, only available to the RKI and have not yet been made public. At the beginning of the epidemic, less than half of the capacity was used. So far, about half a million tests have been carried out – the delay in reporting is several days depending on the region.