You're listening to the Witness Podcast on the BBC World Service. Today we're taking you back to August

1978 and an outbreak in the UK of a deadly virus, smallpox, which the world thought had been successfully eradicated a year earlier.

In 2014, Claire Bowes spoke to the man who diagnosed the last case of smallpox.

It's August 1978 and Professor Alisto Gedders, the smallpox consultant at East Birmingham Hospital in England, gets a call from a colleague.

It was just before an August bank holiday and I was in fact on holiday.

I can even remember what I was doing at the time. I was pulling a cork from a bottle of wine.

And the phone rang and I answered it and this was one of my colleagues and he said, I'd be grateful if you could come and see this patient with a

strange rash which I think may be smallpox.

Very worried Professor Gedders head straight to the hospital to see the patient.

And really as I entered the room it was obvious that this lady had smallpox.

And I very quickly discovered that her occupation was a

photographer in our own school of medicine and of course I knew that research and smallpox was being carried out in that

medical school. The woman's name was Janet Parker. She'd been unwell for more than a week with what she thought was

chicken pox, but Professor Gedders recognised the much larger raised blisters as something

far more serious. Just to be sure, he took samples of Janet Parker's blood

to the research lab at Birmingham University, where his friend Professor Henry Bedson was

head of smallpox research.

So I took the samples across to the medical school, gave him the samples,

and he said, come back in an hour because my electron microscope needs to warm up.

This was the very lab where the small pox virus was held,

the same building where the infected patient Janet Parker worked.

I went back in an hour and the professor was sitting at the electron microscope looking

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