A German man who deliberately got vaccinated for COVID-19 a whopping 217 times did not report any side effects from his many jabs, according to researchers studying possibly the "most vaccinated person in history".

The immune system of the 62-year-old man from the central German city of Magdeburg — who has not been named — is still firing on all cylinders, the researchers said in The Lancet Infectious Diseases journal.

They said the man voluntarily received so many shots against all medical advice, and warned against jumping to far-reaching conclusions from this single case.

The man first came to the attention of the German-led researchers due to news reports in 2022, when he had only received 90 jabs.

Media reports at the time said the man was suspected of getting so many doses to collect the completed vaccination cards, which could then be forged and sold to people who did not want to be vaccinated.

A public prosecutor in Magdeburg opened an investigation into allegations of fraud over the case but no criminal charges were filed, according to the scientific paper published earlier this week.

The prosecutor collected evidence of 130 vaccinations over nine months, it added.

But the man claims to have received 217 vaccine doses of eight different COVID vaccines — including all mRNA versions — over 29 months.

Kilian Schober, a virologist at Germany's University of Erlangen-Nuremberg and study co-author, said in a statement that when they contacted the man, he was "very interested" in undergoing a range of tests to examine the effect of so many vaccinations.

Most Vaccinated Person Ever? 

The case allowed the researchers an extremely rare chance to study what is known as "hyper-vaccination".

Some scientists have theorised that after being hit by so many vaccinations, a body's immune cells would become less effective as they became accustomed to the antigens.

But that was not the case for the German man, the researchers found.

In fact, he had "considerably higher concentrations" of immune cells and antibodies for the COVID virus than a control group of three people who received the recommended three vaccinations, the study said.

His body also showed no sign of fatigue from all those vaccinations — his 217th jab still boosted his number of antibodies against COVID, the researchers found.

The man reported that he never had any vaccine-related side effects from any of the 217 jabs. He also never tested positive for COVID and showed no signs of past infection, the researchers said.

But they warned against taking away any wider lessons from the man's experience.

"It should go without saying that we do not endorse hypervaccination," Schober wrote on X, formerly Twitter.

Caitjan Gainty, an expert in the history of vaccines at King's College London not involved in the study, told AFP she had "never come across a historical discussion of someone who received more vaccinations than this".

It is "relatively unlikely" that anyone has ever had more vaccinations than the man, she added.

Spyros Lytras, a virologist at the University of Tokyo, said it was a "comically large number of vaccinations".

"Whether this is the most vaccinated person in history, I cannot know, but they are certainly the most vaccinated person reported to date" by some margin, he told AFP.

"And I doubt that we're going to see another such report any time soon."