A 62-year-old man in Germany determined to get 217 Covid-19 vaccinations over the course of 29 months —for “private reasons.” But, considerably surprisingly, he does not appear to have suffered any unwell results from the extreme immunization, in keeping with a newly published case study in The Lancet Infectious Diseases.

The case is only one particular person, after all, so the findings cannot be extrapolated to the overall inhabitants. But, they battle with a broadly held concern amongst researchers that such overexposure to vaccination might result in weaker immune response. Some consultants have raised this concern in discussions over how regularly individuals ought to get Covid-19 booster doses.

In instances of power publicity to a disease-causing germ, “there is an indication that certain types of immune cells, known as T-cells, then become fatigued, leading to them releasing fewer pro-inflammatory messenger substances,” in keeping with co-lead research creator Kilian Schober from the Institute of Microbiology – Clinical Microbiology, Immunology and Hygiene. This, together with different results, can result in “immune tolerance” that results in weaker responses which are much less efficient at combating off a pathogen, Schober defined in a information launch.

The German man’s excessive historical past of hypervaccination appeared like a very good case to search for proof of such tolerance and weaker responses. Schober and his colleagues discovered of the person’s case by way of information headlines—officers had opened a fraud investigation towards the person, confirming 130 vaccinations over 9 months, however no felony fees had been ever filed. “We then contacted him and invited him to undergo various tests in Erlangen [a city in Bavaria],” Schober stated. “He was very interested in doing so.” The man then reported an extra 87 vaccinations to the researchers, which in complete included eight totally different vaccine formulations, together with up to date boosters.

The researchers had been in a position to gather blood and saliva samples from the person throughout his 214th to 217th vaccine doses. They in contrast his immune responses to these of 29 individuals who had obtained a typical three-dose collection.

Throughout the dizzying variety of vaccines, the person by no means reported any vaccine uncomfortable side effects, and his medical testing revealed no abnormalities associated to hypervaccination. The researchers performed an in depth take a look at his responses to the vaccines, discovering that whereas some points of his safety had been stronger, on the entire, his immune responses had been functionally much like these from individuals who had far fewer doses. Vaccine-spurred antibody ranges in his blood rose after a brand new dose however then started declining, much like what was seen within the controls.

His antibodies’ potential to neutralize SARS-CoV-2 gave the impression to be between fivefold and 11-fold greater than in controls, however the researchers famous that this was because of the next amount of antibodies, no more potent antibodies. Specific subsets of immune cells, specifically B-cells skilled towards SARS-CoV-2’s spike protein and T effector cells, had been elevated in contrast with controls. But they appeared to operate usually. As one other kind of management, the researchers additionally regarded on the man’s immune response to an unrelated virus, Epstein-Barr, which causes mononucleosis. They discovered that the unbridled immunizations didn’t negatively influence responses to that virus, suggesting there have been no unwell results on immune responses typically.

Last, a number of sorts of testing indicated that the person has by no means been contaminated with SARS-CoV-2. But the researchers had been cautious to notice that this can be because of different precautions the person took past getting 217 vaccines.

“In summary, our case report shows that SARS-CoV-2 hypervaccination did not lead to adverse events and increased the quantity of spike-specific antibodies and T cells without having a strong positive or negative effect on the intrinsic quality of adaptive immune responses,” the authors concluded. “Importantly,” they added, “we do not endorse hypervaccination as a strategy to enhance adaptive immunity.”

This story initially appeared on Ars Technica.