Corona current
Positive test after vaccination: how can that be?
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A positive corona test creates uncertainty – especially if you have already received a vaccination. How is it that vaccinated people also test positive for the coronavirus?
The corona vaccinations are the way out of the pandemic. The vaccinations are currently picking up speed, and at the same time there are more self and rapid tests than ever before. But what if you have already been vaccinated – but still test positive for the coronavirus?
Corona outbreaks among vaccinated people have been causing uncertainty for several weeks. For example, infected people were repeatedly reported in nursing homes, even though the residents had already been vaccinated against the virus. So more and more people are asking themselves how it could be that the corona test turns out positive even though one is vaccinated. With Prof. Dr. Thomas Löscher from the Professional Association of German Internists, BDI eV.
How can a corona test be positive after vaccination?
There are several reasons why a corona test can be positive despite a vaccination:
On the one hand, one has to distinguish between the first and second vaccination in terms of protective effect: “All currently available COVID vaccinations take 1-2 weeks to work and the body has built an immune response. If you become infected during this time or before the vaccination, an infection with or without illness can occur“, explains Prof. Dr. Löscher.
With the active ingredient BionTech, according to the Robert Koch Institute, for example, it is assumed that full protection of 95 percent is only given seven to fourteen days after the second vaccination. At AstraZeneca, protection is 80 percent two weeks after a second vaccination. However, there are studies here that the vector vaccine already protects 95 percent against hospitalization due to Covid disease after the first vaccination.
Both vaccinations therefore offer a very high level of protection, but not one hundred percent. There is still a risk of getting infected with the coronavirus, especially if you have only had a vaccination.
On the other hand, in rare cases, even fully vaccinated people can have a positive corona test if they have come into contact with the virus. Then the symptoms are usually mild or completely. The vaccination trains the body to produce appropriate antibodies when it comes into contact with the coronavirus. However, if this process has not yet been completed at the time of testing or not all viruses can be fully combated, the test may be positive. “Then there are the different variants or mutants. The protection is sometimes worse depending on the mutant “says Prof. Dr. Extinguisher. No meaningful data on the protection of individual vaccines against variants would yet be available here.
The Robert Koch Institute assumes that, according to the data available so far, the risk of spreading the coronavirus if you have already been vaccinated is low, but not zero. This means that people can in principle still be infectious even after vaccination – however, their viral load should be greatly reduced and the virus excretion shortened. So they should no longer play an “essential role” in the epidemiology of the disease.
What do I do if I am vaccinated but test positive?
Even if the risk of infecting yourself and others with the coronavirus is very low after the vaccination, it is strongly recommended that you continue to adhere to the corona rules. The fight against pandemics currently also includes regular corona tests. To be on the safe side, these should also be accepted by vaccinated people. What to do if the test is positive “If a COVID antigen rapid test is positive in a vaccinated person, a PCR test must be carried out immediately. If this is positive, this must be reported and a vaccinated person must be in isolation for at least 10 days in order not to infect others”, explains Prof. Dr. Extinguisher on.
Sources used: Robert Koch Institute, Redaktionsnetzwerk Deutschland