Thomas Kwan, 53, passed himself off as a nurse and even took his own mother’s blood pressure before administering poison to her then partner Patrick O’Hara in Newcastle, northern England.

O’Hara survived but suffered from necrotising faciitis, a potentially fatal flesh-eating bacterial infection, after receiving the jab. He also underwent multiple operations.

Kwan, a family doctor in Sunderland, pleaded guilty to attempted murder last month shortly after his trial began at Newcastle Crown Court. He had previously admitted a charge of administering a noxious substance.

Judge Christina Lambert sentenced Kwan to 31 years and five months in prison for what she described as “an audacious plan to murder a man in plain sight”.

She told Kwan that his plan involved him “abusing your knowledge of the healthcare system”, adding that his actions damaged public confidence in the healthcare profession.

Britain’s Crown Prosecution Service said in a statement after the sentencing that O’Hara was injected with “an as-yet unconfirmed toxin”.

‘Stranger than fiction’

Prosecutor Peter Makepeace told jurors on the first day of Kwan’s trial: “Sometimes, occasionally perhaps, the truth really is stranger than fiction.”

He said Kwan was concerned about his mother’s will, which provided that her house would be inherited by O’Hara if he was still alive when his mother died.

“Mr Kwan used his encyclopaedic knowledge of, and research into, poisons to carry out his plan,” Makepeace said.

“That plan was to disguise himself as a community nurse, attend Mr O’Hara’s address, the home he shared with the defendant’s mother, and inject him with a dangerous poison under the pretext of administering a COVID booster injection.”

Kwan checked into a hotel under a false name, used false number plates on his car and disguised himself with a wig to carry out the plan, Makepeace added.

After Kwan was arrested, police found in his home a large number of castor beans and a recipe for manufacturing ricin, a biological toxin made from the beans. Exposure to as little as a pinhead amount of ricin can cause death.

A chemical expert concluded O’Hara was not injected with ricin, however.