Dr Michael Ryan was at home in his kitchen in Galway one day, and his phone rang. The caller identified himself as Bill Gates.
Thinking it was a wind-up he hung up.
But it was Bill Gates.
That call began a professional relationship that saw the vaccination of 37 million children, saving countless numbers from paralysis and death.
Dr 'Mike' Ryan (55) is the executive director of the World Health Organisation's (WHO) Health Emergencies Programme.
His daily briefings of the current coronavirus pandemic have won him admirers all over the world.
He wisely counselled governments last week.
"Be fast, have no regrets. You must be the first mover. The virus will always get you if you don't move quickly," Dr Ryan said. "If you need to be right before you move, you will never win."
He has been at the forefront of managing acute risks to global health for nearly 25 years.
He grew up in Charlestown in Mayo. His dad was a publican and following his death in the 1970s when Michael was around eight, the family moved down the road about 5km to Curry, Co Sligo.
But both counties want to claim him.
Councillor Gerry Murray grew up with the Ryan brothers in Charlestown. He describes them as "sound, easy-going, lovely lads".
"They would all be decent and would still have a connection to the area. Michael came back here to a talk a few years ago on the likelihood of a pandemic. His mother lives nearby, she's a lovely woman. They've all done very well for themselves, but they wouldn't be the kind to shout about it.
"Mike is a very approachable fella. You should give him a ring."
We did put a request to the World Health Organisation (WHO) but haven't heard back yet.
Dr Ryan studied medicine in NUI Galway and later trained as a surgeon specialising in orthopaedics and trauma. He married fellow doctor Maura Connolly, and they live in Galway city with their two teenage sons.
It was during a 12-week humanitarian trip to Iraq in 1990 that he was severely injured when the car he was travelling in was run off the road by a military convoy.
He broke his back in three places, which led to the end of his surgical career.
His brother Coley Ryan, a well-known and successful publican and restaurateur in Massachusetts, said the accident changed the direction of his life.
"He trained in Ireland, he only got into public health because he was involved in an accident in the Iraq War.
"He had his back broken in several places and unfortunately he wasn't able to continue with his surgery. So that was 1990. He then went to work in public health and studied epidemiology," he said.
Coley said he is accustomed to seeing his brother on TV but is conscious that his role during the current crisis is very high profile.
"He lectures in some of the universities here (in America), and I would always attend those. So I'm used to seeing him on TV and reading about him. But this is obviously high profile, and he is under a lot of pressure. He is the right guy to deal with it, though.
"He has been talking about this for a long, long, long time, about the chances of something like this happening.
"We haven't had a worldwide pandemic since 1968 and then back to 1918."
He said the new coronavirus had caught them by surprise to a degree.
"But in all honestly they have been trying to prepare people for it for a number of years. Bill Gates, who Michael also works for, has been warning the world. Unfortunately, people, it doesn't matter how much we prepare, it still wouldn't be enough. It depends on what we do now."
On the question of whether Mayo or Sligo can claim Dr Ryan, Coley said the answer was not clear cut.
"Here is the deal. He spent the first 10 years of his life in Charlestown, Co Mayo, then we moved to Curry, Co Sligo.
"So he's from both places. And proud to be. Michael has a lot of stories over the years. He would have a lot of encounters with famous people.
"A lot of these philanthropists, they want to do their best and Bill Gates and Warren Buffet would definitely be like that."
He said they have been very helpful with polio.
"Michael took a two-year sabbatical and led Bill Gates's attack on polio which had an outbreak due to the wars in Afghanistan and Syria. So they vaccinated 37 million children.
"All I can tell you is I'm very proud of him. We're all proud of him, and we're all behind him.
"He has always been a humanitarian. He never got into medicine for the money, that's for sure. It's a vocation, and he has followed that principle all the way."
He said his brother had lived most of his life in and out of Africa fighting diseases such as Ebola.
"He always worked in the field. He just came back to Geneva in the last number of years. He worked in the field for polio in Afghanistan, Pakistan, Syria and Lebanon.
"Anything you could write about him would be positive because he is one of those people," he added.
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