Tom Catena, M.D., has been described as ”the world’s most important doctor,” and he is, to more than a million patients.

That’s because the 55-year-old American doctor is the only surgeon for 1.3 million people in the Nuba Mountains of Sudan—a region nearly twice the size of Massachusetts. A Catholic medical missionary in a region torn apart by war, he was just awarded the annual Gerson L’Chaim Prize for "outstanding Christian medical missionary service" from Florida-based nonprofit African Mission Healthcare.

RELATED: This 'country doctor' protects bygone era in medicine—and access in remote California town The international medical missionary prize comes with a $500,000 award—money Catena plans to use to cover some of the running costs of his hospital and to help establish a school to train nurses, midwives and clinical officers (the equivalent of physician assistants in the U.S.).

“The $500,000 goes a long way here,” Catena said via email to FierceHealthcare. “We feel the school is key to just start creating a cadre of trained Nuba health professionals.”

Tom Catena, M.D., with a mother and young child

(African Mission Healthcare)

Catena, who grew up in upstate New York, has served in Africa for more than 20 years. Since 2008, he has practiced in Gidel in the Nuba Mountains, living in the middle of the war-torn and besieged territory, which is fiercely contested by its inhabitants and the former government of Sudan.

“The two things that keep me here are the toughness and resilience of the Nuba people and what I see as my role as a medical missionary,” he said.

“My role is simply to show the love of Christ to others and that can only be done by sticking it out during the times that are most difficult.”

In 2011, when the fighting started in Sudan and the capital began bombing its own people in the southernmost region, all of the other expatriate workers in the country left, he said. It was the missionaries who stayed with the people.

Catena was among those who insisted on staying. A graduate of Duke University Medical School and a former U.S. Navy doctor, Catena has been the medical director at Gidel Mother of Mercy Hospital, which he helped establish.

The 435-bed Catholic hospital is the only major medical facility in the Nuba Mountains, and Catena is on call 24/7, sometimes seeing as many as 350 or more patients in a single day.

At one point subject to bombings by Sudanese fighter jets, the hospital compound now has several foxholes where patients and staff can flee in case of more attacks.

A deserving recipient

The L’Chaim (Hebrew for “to life”) Prize is sponsored by Jewish philanthropists Rabbi Erica and Mark Gerson.

“Dr. Tom Catena has given up everything that we in the U.S. take for granted in order to bring healthcare to more than a million people who, without him, would otherwise not have access to any medical care,” said Mark Gerson, co-founder of African Mission Healthcare, which has been supporting mission hospitals in Africa since 2010, in an announcement about the 2019 award.

The L’Chaim prize, launched in 2016, comes with the world’s largest annual award of its kind dedicated to direct patient care in Africa. Catena will receive the award April 14 at a dinner in New York City.

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“For more than a decade, Tom has endured bombings, epidemics, rainy seasons and flooding, loss of power, lack of equipment and staff, and very little connection with the outside world, all because of his dedication to the Nuba people. He exemplifies what it means to ‘walk in all God’s ways and to love Him,’ and we are honored to be his partner in his sacred work,” said Rabbi Erica Gerson, who co-sponsors the prize with her husband.

The $500,000 award will go toward the Nuba 2020 campaign, the goal of which is to raise $7.5 million to keep the only major hospital in the Nuba Mountains fully operational for the next two decades. The money also will help strengthen and expand the hospital and its network of clinics, Catena said.

Mark Gerson commented on Catena’s commitment. “The sheer amount of good he does—as measured in clinic visits, surgeries, deliveries, community clinic patients treated, and children vaccinated—with the amount of resources he has is completely stunning. It is simply incredible to even think about how many lives Tom and the team he has built can save and transform with the money that he is provided,” he said.

A challenging place

Catena, who has also had his face on a 2018 Armenia stamp after he was awarded the second annual Aurora Prize for Awakening Humanity, said he was pleasantly surprised to receive the L’Chaim prize.

“The previous awardees had pretty major accomplishments,” he said. “The prize money will give us a big boost and hopefully help to put us on some solid financial footing. We are completely dependent on individual donors yet are the only major referral hospital for a population of over one million.”

Tom Catena, M.D., with his wife Nasima,

a nurse (African Mission Healthcare)

Catena said it is the people who have kept him in Africa. He recalls a young girl, who was about three or four years old and was being cared for by her elderly grandmother. The girl’s mother was killed in an airstrike by the Sudan Air Force, and the grandmother was struggling to look after her.

“When the girl came to us, she was skin and bones and unable to walk due to TB of the spine. With TB medicines and good care by our nursing staff, the girl was restored to full health,” he said.

His advice for other doctors? “Working in these remote and challenging settings can be very frustrating yet incredibly rewarding,” he said.

But it’s work he recommends others try. “I’d recommend anyone to do perhaps a short-term mission to see if it’s for them and then something more long term, where they would be able to contribute more.”