The victim was walking barefoot through grassland when he felt a sharp pain in his foot, the Telegraph reported, quoting victim's friend Kim Needham.
He was admitted to Boston Pilgrim Hospital in a critical condition with "blood poisoning", she said.
The victim is now recovering after "sting" was removed, but the exact cause has not been disclosed, the paper said.
In a response to a concerned comment, she added: "He is fine now, but it was touch and go though, as they had to cut the sting out of his foot."
No official details about the incident have been released, the paper added.
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