After COVID-19 you are probably immune for one to two years
Based on the current state of knowledge, several experts are of the opinion that people who have had a COVID-19 disease are initially immune.
Research is underway at Sars-CoV-2. The virus has only been around for a few months - not much is known yet. According to experts, however, it is likely that people will be immune once they have been infected.
Immunity to the SARS-CoV-2 coronavirus
According to experts, people who have survived an infection with Sars-CoV-2 are probably initially immune to the pathogen. As is known today that humans form antibodies after being infected with the novel corona virus, explained virologist Melanie Brinkmann from the Helmholtz Center for Infection Research in Braunschweig and Friedemann Weber, head of the Institute of Virology at the University of Gießen. It can be assumed that immune protection will last one to two years after infection. This assumption is based on experience with other human corona viruses.
Long-term investigations are not yet possible
"In all likelihood, after being infected with the Sars CoV-2 virus, you are protected against re-infection for at least a few years," said the President of the German Society for Immunology, Thomas Kamradt. However, this cannot be said exactly, after all, antibody tests are only just coming out and long-term studies are still not possible, since the disease has only been known for a few months. According to what is known about similar viruses, the antibodies formed as a reaction by the body protect against re-infection.
How long do antibodies provide protection?
According to Kamradt, how long this protection lasts depends on the rate at which the concentration of antibodies in the blood, the so-called antibody titer, decreases. The higher the titer, i.e. the number of antibodies, the stronger the protection. It would be "extremely unusual" that the antibodies produced against the novel corona virus in the body do not protect against renewed infection, said Kamradt.
Concentration of antibodies is crucial
According to Matthias Orth, medical director of the Institute for Laboratory Medicine at the Marienhospital Stuttgart, it is not yet possible to say with certainty whether the antibodies formed will protect against re-infection. It is still unknown at what concentration of antibodies there is protection and how often infections still occur.
According to Brinkmann and Weber, it will also be interesting to study the antibody titers of people with different disease courses. This clarifies the question of whether people with severe courses had formed antibodies at all - or in other words: "Was the course so difficult because no antibodies were yet available?" It was also possible to answer the question of when specific antibodies are formed in the course of the infection .
Tests could determine basic immunity of the population
According to Brinkmann and Weber, it is now important to identify reliable antibody tests and to test them across a wide area. This is important in order to determine the undisclosed number of unrecorded cases. This helps to recognize how many people have already gone through the infection unnoticed, i.e. how high the basic immunity of the population is already.
According to statistical projections, around 60 to 70 percent of the population must have been infected before the pandemic wave comes to a standstill on its own - that is, without protective vaccination. Knowledge of a past infection is also important in order to give people with existing immune protection the “green light” for work and for lifting the contact reduction.
When do antibodies form?
According to the Berlin virologist Christian Drosten, it takes about ten days for antibodies to form after an infection with the corona virus. A blood test with a specific test can then be used to measure whether a patient has antibodies in the blood, "regardless of whether they had a severe infection or a mild infection or a completely unnoticed infection," Drosten said in an NDR podcast last week. The latter are also antibody positive. (vb; source: dpa)