What you need to know about coronary tests

Updated on 4/28/2022 at 5:17 pm

  • Corona tests have been with us for a long time.
  • Even after relief, they are important to many people in daily life.
  • Ten things to know about fast tests, self and PCR.

Here you can find more health topics

Most of them have probably heard from at least one person in their circle of acquaintances, who suddenly had Corona, despite some rapid tests and negative PCR. Federal Finance Minister Christian Lindner also recently became infected with Sars-CoV-2 – after rapid tests on the same day and the day before had given him a negative result.

But how reliable are rapid tests and PCR in relation to Omikron? Should it be better to take samples from the oral cavity during the self-test? Now you need to know these ten things about coronary tests.

1. Under certain conditions, anyone can do a free PCR and fast test.

All citizens in Germany are entitled to at least one free quick test per week. The situation is different with PCR tests. People who

  • a rapid positive coronary test or
  • a positive autotest or
  • specific coronary symptoms and doctor’s order
  • have been designated as contact persons by the authorities

can do free PCR tests. Exceptions and special cases apply, for example, to people working in care institutions or similar (further details: https://www.zusammengegencorona.de/faqs/testen/allgemeine-infos-zum-testen/) Important to know: Although In PCR testing, risk groups, employees of medical and vulnerable areas have priority, but other groups also have the right to test.

2. Coronary tests also reliably detect omicron infections.

At the request of our editors, the Paul Ehrlich Institute stated: “The investigations targeted by the Paul Ehrlich Institute allow the conclusion that there is no evidence of weaker detection of the omicron variant by antigen tests.” In Germany, the corona virus is usually detected using the so-called N protein (nucleo protein) of the corona virus. Although Omicron has mutations in the N protein, this does not play a crucial role in the tests.

3. However: Not every self-test and quick test is just as reliable. Here you can see how reliable your corona test is.

A list from the Paul Ehrlich Institute (PEI) shows how reliable the various rapid coronary tests and self-tests are. The PEI has examined the various coronary tests and has listed in this table how good the test is.

4. The susceptibility of a corona test indicates the percentage of a test that can detect an infection in an infected person.

Therefore, sensitivity is an important benchmark. The PEI classifies a test as reliable by an overall sensitivity of at least 75 percent. By the way: Viral load plays a crucial role in sensitivity. If a test has a high probability of “jumping” even with a low viral load, this increases overall sensitivity. Therefore, sensitivity is an important factor for the functionality of a corona test.

5. When the viral load is low, the tests themselves, rapid and even PCR may not show an existing infection.

It is possible that, in addition to independent and rapid tests, PCR tests, which are often declared the “gold standard”, give a false negative result. By itself, laboratory testing is very reliable. However, sampling time plays a big role. Immediately after an SARS-CoV-2 infection, the viral load may still be so low that even a PCR test cannot detect it. In this context, the Robert Koch Institute writes: “Testing twice or with a time delay (eg on days 5 to 7 after exposure) increases the relevance and significantly reduces the residual risk.”

6. If the PCR test is positive, the Ct value reveals how contagious you are still. With a value of at least 30 cents you can leave the isolation after seven days.

At zusammengegencorona.de, an offer from the Federal Ministry of Health states: A Ct value of 30 means that 30 measurement cycles were needed to detect the coronavirus in the sample. The more cycles to be performed, the lower the viral load. It is assumed that the infected person is no longer contagious with other people when the Ct value is high.

7. Self-tests should be performed exactly as instructed on the packaging.

Among other things, make sure the quick test is stored at home at room temperature. Experts advise not to fully blow your nose before testing. Important to implement: Be sure to insert the rod into both holes.


Anyone in Germany can still be tested for the corona virus with a quick test. Should this end soon? Thumbnail: photo alliance

8. For nasal self-tests, throat sampling is not recommended.

Nasal self-testing should not be performed in the mouth. The U.S. Food and Drug Administration even issued a warning earlier this year. Speaking to CNN, an FDA spokesman said self-testing in the smoking area is more complicated and can lead to injury if treated poorly. Throat tests are recommended only by trained personnel. At the request of our editors, the Federal Ministry of Health refers to

9. According to the Infection Protection Act, a rapid positive antigen test should be reported – but not a positive self-test.

As before, the local health department should be informed if a prompt antigenic test performed by specialist staff is positive.

Corona in the retina

According to new findings from the Max Planck Institute, coronaviruses can also multiply in the retina.

10. A negative corona test represents only one photograph.

As already mentioned, a negative test does not necessarily mean that you are not infected with Corona, but that the viral load is very low. In any case, the result should not give you a false sense of security. On the contrary, experts and official bodies recommend compliance with the basic rules of hygiene and AHA rules.

Resources used:

  • Responds in writing to a request to the Paul Ehrlich Institute
  • Responds in writing to a request to the Federal Ministry of Health
  • Paul Ehrlich Institute (21.04.22)
  • gesundheit.gv.at (27.04.22)
  • gegencorona.de (27.04.22)
  • Federal Ministry of Health (21.04.22)

Leave a Comment