Darrick Robles While we are in lockdown and the first ones have already been vaccinated, many people have already gone through the coronavirus infection. Are you now immune to the virus? Can you get Covid-19 again? And how dangerous are coronavirus mutations? This is the current state of research on Covid-19 and immunity.
What does immunity mean?
We can be immune to pathogens: This means that our body can fight off these pathogens without us feeling any symptoms of the disease. We can acquire immunity after a previous infection or through vaccination – but this does not apply to all pathogens. After a measles infection we are immune for life, but we can get flu again and again. How long we are protected by antibodies varies from disease to disease.
What does research say about Covid-19 and immunity?
A long-term study by the University of Oxford examined more than 12,000 healthcare workers. They were regularly tested for antibodies between April and November 2020. Antibodies indicate that you have been infected with corona viruses before. Of a total of 1,246 participants with antibodies, none showed a re-infection with symptoms. Only 3 of them tested positive for Covid-19 . Therefore, the Oxford study assumes that immunity lasts for at least 6 months.
We are currently unable to give a clear answer as to how long immunity lasts overall. In addition, the immune response can be different for everyone – and not everyone infected with Covid-19 produces enough antibodies.
How dangerous are virus mutations?
Viruses mutate all the time. We call mutations small changes in the genetic material. We currently know of 12,000 mutations that the SARS-CoV-2 coronavirus has already undergone. Most mutations do not affect how well the virus can spread or how severe an infection is. However, there are also mutations that can make the virus more contagious – presumably because they change the spike proteins (“spines”) of the virus and thus make it more capable of binding. Such coronavirus mutations have been detected for the first time in Great Britain, Brazil and South Africa since the end of 2020.
In Germany, most coronavirus infections now go back to the British variant B1.1.7. It is even easier to transmit than the SARS-CoV-2 original type. So far, however, there is no evidence that it could greatly reduce the effectiveness of the vaccines .
How does our immune system react to the corona virus?
If you become infected with SARS-CoV-2, your immune system can produce antibodies that render the coronavirus harmless. In the second week after the onset of the disease, the antibodies can be detected in a laboratory test. However, not everyone who has had a corona infection has antibodies in their blood.
In addition, your body can produce so-called T-cells. They belong to the white blood cells and play a central role in the immune response. Helper T cells control the immune response, killer T cells recognize and destroy infected cells. A T-cell immune response also occurs in Covid-19 patients without antibodies – a finding that is also important for vaccine research.
How likely is it to become infected again?
It is assumed that immunity is built up differently from person to person. And because the coronavirus adapts and can mutate, some people get infected a second time, both with and without symptoms. You can never rule out reinfection with SARS-CoV-2.
Can I infect others despite surviving the infection?
Reinfections are not yet sufficiently documented to make a general statement. However, there are known cases in which Covid 19 patients have become infected again and have shown symptoms again. The risk of infection is therefore not out of the world even after the illness has been overcome. If you suspect an infection, our Covid-19 symptom check can give you more clarity. Always follow the recommended hygiene measures to protect yourself and others.
