A 62-year-old man from Germany has, against medical advice, been vaccinated 217 times against COVID.
The bizarre case is documented in The Lancet Infectious Diseases journal.
The shots were bought and given privately within the space of 29 months.
Researchers from the University of Erlangen-Nuremberg say the man appears to have suffered no ill effects.
Dr Kilian Schober, from the university's microbiology department, says they learned about his case via newspaper articles.
He says they then contacted him and invited him to undergo various tests in Erlangen, and he was very interested in doing so.
The man provided fresh blood and saliva samples, and researchers also tested some frozen blood samples of his that had been stored in recent years.
Dr Schober says they were able to take blood samples themselves when the man received a further vaccination during the study at his own insistence.
He says they were able to use these samples to determine exactly how the immune system reacts to the vaccination.
Evidence for 130 of the jabs was collected by the public prosecutor of the city of Magdeburg, who opened an investigation with the allegation of fraud, but no criminal charges were brought.
COVID-19 vaccines cannot cause infection but can teach the body how to fight the disease.
BBC
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