Judging by the activity on social media, many of the more than 20 million unvaccinated people in the country are apparently concerned with the question of whether an infection with Omicron could, in a way, pay off for them. The infection, which according to this reading is usually “mild”, will strengthen your own immune system and thus accelerate the end of the pandemic. It is this hope - the "harmless" omicron virus as a kind of vaccine substitute - that Federal Health Minister Karl Lauterbach and Charité virologist Christian Drosten warned about a few days ago. Omikron will by no means offer sufficient protection against other virus variants next autumn.The debate about a possible omicron immunity is also about the future of the vaccination campaign, which is once again faltering, and also about the benefit of a cross-party attempt to introduce compulsory vaccination.

Joachim Müller-Jung

Editor in the feuilleton, responsible for the "Nature and Science" department.

  • Follow I follow

So what does the omicron wave do?

Who comes out of it well, and what comes after?

One thing is clear: statistically, the risk of becoming ill is many times greater for unvaccinated people with an omicron infection than after the triple vaccination.

The study by the South African virologist Alex Sigal with omicron-infected people, which was published at the end of December and has since been updated again, has caused some confusion.

According to the conclusion, the omicron wave with several million new infections worldwide could finally replace the more dangerous delta variant.

According to the thesis, anyone who gets infected with Omikron also builds up immune protection against Delta.

However, it is a very far-reaching conclusion for a small study with a few dozen diseased subjects.

The data is only clear in one respect: those who were vaccinated before the omicron infection and experience a breakthrough infection will feel the booster effect.

The amount of neutralizing, i.e. virus-killing, antibodies increases many times over.

And they sometimes protect vaccinated people in the laboratory experiment better from Delta than from Omicron itself. In the case of the test subjects referred to as “unvaccinated” in the South African study (how many had possibly been infected with the beta variant long before that remained unclear), there were there is a significantly poorer antibody protection against the delta virus after the omicron infection.

Can potentially deadlier variants emerge?

Overall, the antibody response after omicron infection was significantly weaker in all subjects than after delta infections, which is also the price of a milder disease: the immunity level after omicron is generally lower, the production of effective antibodies and also the number of those protecting against severe disease T cells were already significantly weaker in earlier waves after mild or symptom-free courses. In addition, the results only apply to the current Delta version. What if other aberrantly mutated variants, distinct from Delta and Omicron, emerge in the coming months? Then, roughly speaking, the omicron defense weapons may no longer be effective against the new pathogens. In any case, future cross-immunities cannot be predicted.Even after the analysis of thousands upon thousands of individual mutations, it is by no means clear whether, in the course of the parallel, global evolutionary dynamics, more highly pathogenic, potentially more deadly variants may not emerge again in the coming months.

In any case, the risk of this does not decrease with the powerful omicron wave.

New, strongly deviating variants arise most easily when the virus multiplies for months in the body of immunocompromised people, can deal with the defense and exchange genetic material.

And: The larger the total number of infections in the population (i.e. the higher the waves), the higher the probability of variants with immune escape and/or easier transmissibility.

Efficacy of vaccination after booster at over 90 percent

Omicron itself is the best proof of how radically such multiple mutants can evade the defense. Already at the end of December - one month after the appearance of Omikron - it had been shown in many published experiments that only a few of the artificial, monoclonal antibodies produced specifically against the first virus variants - vital and expensive emergency drugs for seriously ill and immunosuppressed patients - the Omikron - Render virus harmless.

It also remains unclear how long the immune protection built up by Omikron lasts. As with previous variants, this should also depend on the strength of the immune defense reaction and thus on the severity of a Covid 19 disease. In other words: If you are not vaccinated, become infected with Omicron and hardly notice it, you cannot hope for long-lasting immunity. It's different for those who have been vaccinated three times. Even the booster dose increases the effectiveness of the vaccination in the first few months to the level of the vaccine approval - beyond ninety percent. If an omicron infection occurs, the immune response is further broadened, and the cross-immunity built up in this way presumably lasts longer. A few preliminary studies from Delta times indicate that a sufficient,"Boosted" immunity - depending on age and previous illnesses - could be maintained for more than eight months.