SElten was no more surprised by an announcement by the Standing Vaccination Commission than the one that chairman Thomas Mertens first made on a talk show: Stiko would recommend boosting all adults. Two days later the time had come, because the corona pandemic was not over with one or two vaccine doses per person. All adults whose basic immunization against Covid-19 was around six months ago should now get a booster vaccination. So far, this only applied to people over 70 or with an immunodeficiency, as well as to medical staff. The Federal Ministry of Health declared booster vaccinations to be a top priority. Currently around 4.8 million adults have been vaccinated three times, and by the end of the year it should be 15 million.
There is now a boost against the fourth wave because the effect of the vaccine wears off after a few months. Studies have shown that, and this is now being observed in hospitals, in which the more contagious Delta variant, to which almost all new infections in Germany can be traced back, exacerbates the situation. Couldn’t vaccines targeting Delta help?
Research on Covid vaccines is in full swing in the background. Companies such as BioNTech and Moderna are working on modified versions of their vaccines that are set for certain variants, some are designed for booster vaccinations. Other companies and research groups are developing completely new vaccines. Have the old ones already served their purpose? Will there be a bunch of vaccines soon, all of which protect against different variants?
The immunologist Reinhold Förster from the Hannover Medical School made it clear in an interview: The vaccines that are currently available against Covid-19 are very effective. However, it did not surprise him that two vaccine doses are not enough to generate permanent immunity: “Take a look at the Stiko vaccination calendar,” he says, referring to the vaccinations that are mostly given as a child – measles, hepatitis -B, pneumococci. “You can see that with many vaccinations three basic immunizations are required within the first year.” And some would have to be refreshed later.
More antibodies after the booster than after the second vaccination
In Germany, many were vaccinated against Covid-19 in early summer, now they are running out of this protection. This also shows a Study from Sweden, which was pre-published in the journal “The Lancet” at the end of October and has not yet been reviewed. The illness data of more than 800,000 vaccinated persons indicate that the effectiveness of the vaccinations can hardly be proven after about seven months, even if the protection against a serious illness lasts longer. Do we need a shot every few months now? Förster thinks it is possible that you can be vaccinated against Covid-19 in a manner similar to that against influenza, once a year. Hope is provided by data from Israel: There, after the booster vaccination with the BioNTech / Pfizer vaccine, significantly more antibodies were detected in employees of the Sheba Medical Center near Tel Aviv than after the second injection. Similar results were found in England with the AstraZeneca vaccine. “So you can assume that the vaccination protection will last longer,” says Förster. He himself is working on a new vaccine against Covid-19 – for inhalation. When a vaccine is put into the muscle, it induces a good immune response – but also a wrong one, says Förster, in the sense that certain antibodies first have to be transported to where they are primarily needed: into the respiratory tract. “One idea would be to induce mucosal immunity, so that there are a lot of antibodies against the spike protein on the mucous membranes of the airways.” In the preclinical studies, rodents have so far inhaled this Covid-19 protection and tolerated it well . The human clinical trial could begin this year. However, it is more complex to nebulize a preparation in a nebulizer and inhale for minutes than to receive a spade with the syringe. That is why the inhalation vaccination would be more intended for people with immunodeficiency or for risk groups.