One is a Japanese doctor acclaimed for her work promoting the safety of the HPV vaccine. The other is a Vietnamese film-maker, in Britain for the opening of her retrospective at the Institute of Contemporary Arts.

Unfortunately, staff at BBC Radio 4 Woman’s Hour failed to tell the difference between Dr Riko Muranaka and Trinh T Minh-ha.

Cue an excruciating exchange on live radio, in which an oblivious Jenni Murray set about interviewing the wrong person.

After an introduction explaining that Dr Muranaka is the recipient of this year’s John Maddox Prize for promoting science on a matter of public interest, Murray turned to her guest. “Riko, why did you pursue this subject?”

There followed a very long pause.

Murray, a tiny note of anxiety in her voice, tried again. “Why did you pursue this subject?”

“Which subject are you pointing to?” asked a perplexed Trinh.

“The subject of the HPV vaccine. The 20 articles that you wrote on it,” Murray said, clearly wondering why the doctor, journalist and lecturer at Kyoto University School of Medicine was being so obtuse.

“It’s not me,” came the reply.

“I’m sorry?”

“It’s not me,” Trinh repeated, with a nervous laugh. “I guess you got the wrong speaker.”