oming just before the final round of Six Nations matches, Bath’s signing of Nathan Charles from Clermont passed virtually without comment. Arriving on a short-term deal to solve an injury crisis at hooker, it might seem an unremarkable move. Except, that is, Charles is the most remarkable rugby player on the planet.

He was born with cystic fibrosis, a genetically inherited, life-shortening disease that causes persistent lung infections and limits the ability to breathe over time. When he was diagnosed with the condition at three months old, his parents were told that he would not live past the age of 10. Life expectancy these days is now 37.

On Sunday, the 28 year-old travels as a non-playing reserve with his team-mates to Allianz Park for Bath’s Aviva Premiership match against Saracens as the only known cystic fibrosis sufferer anywhere in the world to enjoy a professional career in a contact sport. As former Australia coach Ewen McKenzie said before giving him his international debut, Charles “seems to defy science and logic.”

Not that Charles, who will make his Bath debut next week in the Challenge Cup quarter-final against Brive, takes the same view. “I see myself as a normal bloke living a normal life,” Charles told The Sunday Telegraph at Bath’s resplendent Farleigh House training base.

Every day, he will take between 20 to 30 pills. The medication controls the infections that constantly build up in the lungs while the vitamins maintain his overall health.

“With cystic fibrosis, the slightest cold can just snowball into something a lot worse,” Charles explained. He has to be hyper-vigilant, giving anyone with so much as a sniffle a wide berth.

His parents never held him back from physical activity. In fact, they encouraged him to try his hand at every sport he could. “Their attitude was if you fall, we will be there to pick you up and push you back out there,” he said. “Being active and being outside every day is really important. I genuinely think that exercise is the best medicine - obviously for your lungs but also for your mindset being out there giving it your all.”

Rugby, a sport played by all his family, always held the greatest appeal. “From a young age, I knew this is what I wanted to do.”

His first contract was in rugby league before he switched to union with the Brumbies. Initially, he kept his condition a secret from his coaches and teammates.

“We kept it within the family because it was something that people did not understand,” Charles said. “You read the facts on it and it is not good. I didn’t want to give the coaches a reason or an excuse not to pick me. I didn’t want to be that guy. I always wanted to be a proven player before I came out with it.”

But suspicions began to grow around Charles’s unusual routines. Eventually, Andy Friend, the coach, rang him and asked if he had multiple sclerosis. “I was like ‘I don’t have that - I have CF’,” Charles said.

After a frank conversation, Friend offered reassurances that he would treated exactly the same way. They also agreed that Charles should address the rest of the squad.

“I got up to do my big speech. I was pretty nervous and then I literally couldn’t get a word out before I choked up,” Charles said. “I actually couldn’t talk. I don’t know why and what came over me. I think it was because I had so much respect for the guys in my team that I didn’t want to be viewed in a different way. I was probably scared as well. A lot of emotions came up but once I got myself together I managed to get through it and after that I was a bit embarrassed by what I had said, but every single player came up to me and said anything we can do to help you.”

Charles still does not wish to be defined by his condition or its associated life expectancy. “I have always said that number will not play a role in my life. I have got a lot more years to live and I will live them to the fullest I possibly can.”

Indeed, he would be mortified to be seen as some sort of sob story. “I want to be known as a rugby player who busts his backside and has achieved some great things such as playing for my country,” Charles said. “Making my Australia debut was a proud moment not because I was the first person with CF to get there but because I had worked so hard to get to that spot.”

By publicising his condition, Charles hopes to challenge some of the stigma associated with cystic fibrosis and other debilitating conditions. Each week, he sets aside an afternoon to reply to the dozens of messages he receives from CF sufferers or their families. Sometimes he barely gets through a third of the correspondence.

“It is truly humbling,” Charles says. “On a day-to-day basis I get amazing messages saying how much of an inspiration I am to them, their family or their children. One recent correspondent asked me if I could give them a signed shirt because they want to put it on the wall for their kid who has CF. They want him to see that shirt growing up so they know this is not something that can hold you back. I don’t see myself like that but when you get those messages and realise you have that effect on people it is really mind-blowing.

“It would be amazing if I can be that example whether it is CF or anything else, to not let those barriers define the person that you are or that people should not be judged by their condition. It is how you overcome that condition. I hope I am not just a light of hope to people with CF but to other people who are fighting their own battles.

“If you believe, you can achieve. I really believe in that saying. If you have the correct mindset you can overcome any hurdle or obstacle.”

Charles’s wife, Verity, is a professional netball player in Australia despite having type one diabetes. They share an identical outlook on life.

“We both have our own little things to deal with,” Charles said. “But they are our battles. Everyone in this world has something, whatever it is.

“There is not one person who does not have demons or something to overcome. This is mine. The diabetes is my wife’s. You deal with it and move on. That’s the way we look at life. God has dealt us this hand so there’s no point whingeing and going ‘why me?’ You just have to live life to the best of your ability. That’s the only approach you can take.”(Telegraph)