Two hundred and seventeen. That's how many vaccines a man in Germany claims to have received for COVID-19 in just 29 months – and his body isn't reacting the way some scientists thought it would.
The 62-year-old male from the city of Magdeburg made headlines a few years ago for his private and risky decision to thwart national medical advice and get jab after jab after jab – all allegedly in a bid to sell proof of vaccination cards to unvaccinated individuals.
Researchers in Germany first read about the case in the newspapers. With the man's permission, they are now studying his immune system to see how it's coping with 'hypervaccination'.
While the researchers emphasize that they "do not endorse hypervaccination as a strategy to enhance adaptive immunity", they were curious about the effect that hundreds of vaccines might have on a person.
Scientists have wondered for years now how many vaccinations for COVID-19 people should be getting, and one theory is that too many injections could have downsides, triggering an excessive immune reaction, or, on the flip side, fatiguing immune cells and making them less responsive to the SARS-CoV-2 virus.
The man from Germany is living proof that neither outcome is necessarily the case.
Official records confirm that the individual received at least 130 vaccines for COVID-19, including 8 different vaccine types, in the space of just two and a half years. In fact, the vast majority of these shots were given in a 9-month period.
Nevertheless, his immune system, experts say, is fully functional.
"The observation that no noticeable side effects were triggered in spite of this extraordinary hypervaccination indicates that the drugs have a good degree of tolerability," says immunologist Kilian Schober from the University of Erlangen-Nuremberg (FAU).
Specifically, blood tests revealed that the hypervaccinated individual had a large number of T-effector cells, more so than people who had received just three vaccinations. T-effector cells promote an immune response to SARS-CoV-2.
However, other immune cells, which replenish numbers of T-effector cells, were present in similar quantities in the hypervaccinated man and thrice-vaccinated individuals.
"The number of memory cells was just as high in our test case as in the control group," explains immunologist Katharina Kocher from FAU and a leading author of the study.
None of the man's immune cells appeared fatigued, either. "Overall," Kocher adds, "we did not find any indication for a weaker immune response, rather the contrary."
When the hypervaccinated patient received yet another vaccine whilst under the supervision of researchers at FAU, his antibodies against SARS-CoV-2 increased significantly once again.
This suggests that the vaccine can still have an effect, even after possibly hundreds of previous shots.
Of course, that does not mean that people everywhere should throw caution to the wind and start getting vaccines for COVID-19 on a daily basis.
This is just one case – and an extreme one at that. But it does provide real-world results on the largely theoretical topic of repetitive COVID-19 vaccinations and the benefits, limitations, and risks.
"Current research indicates that a three-dose vaccination, coupled with regular top-up vaccines for vulnerable groups, remains the favored approach," says Schober.
"There is no indication that more vaccines are required."
The study was published in Lancet Infectious Diseases.