Gerard Hammond, an 84-year-old Catholic priest from Philadelphia, in North Korea, a country where he has done humanitarian work since 1995. (Gerard Hammond)

Father Gerard Hammond has been to North Korea 52 times. Or maybe it’s 53. It’s so many times that he’s lost count.

But now, the 84-year-old Catholic priest from Philadelphia fears he may not be able to go again, because of new restrictions on American travel to North Korea that will go into effect Friday.

“I can’t conceive that our country would prohibit humanitarian aid,” said Hammond, the superior of the Korean mission of Maryknoll, the American Catholic Church’s overseas missionary organization. “No country in the world does that.”

The new travel restrictions technically won’t ban American humanitarian workers from traveling to North Korea. They will bar Americans from traveling as tourists and will require others, such as aid workers and journalists, to get a special one-time passport authorizing each trip.

But in practice, Americans like Hammond are concerned that the additional layer of bureaucracy — on top of international sanctions that have made it hard to send medicine and equipment into North Korea, as well as the idiosyncrasies of the North Korean system — will make an effort that is already difficult close to impossible.

Although the regulations will go into effect this week, the State Department was not able to give even a ballpark time frame for how long it will take to consider and issue the special permits.

“Applications will be handled on an individual basis, so we are not able to speculate on how long the process will take,” said Ashley Garrigus, a spokeswoman for the department’s Bureau of Consular Affairs.

[ State Department: U.S. to block Americans from traveling to North Korea ]

That is creating headaches for aid organizations, academics and sports people alike.

The Pyongyang University of Science and Technology (PUST), an American-run private institution, has 10 American passport holders on its campus who are trying to figure out how to teach during the fall term, which starts Monday.

“The U.S. citizens working at PUST are eagerly praying and waiting approval of the State Department to return to PUST,” said Park Chan-mo, the university’s chancellor.

George Vitale, a retired New York City police officer who introduced taekwondo, the South Korean martial art, to North Korea, is waiting to find out if he will be permitted to attend the International Taekwon-do Federation world championships, due to be held in Pyongyang in mid-September. Vitale, who has promoted taekwondo as a form of “ping pong diplomacy,” helped North Koreans participate in a competition in the South in June for the first time in a decade.

The restrictions are being imposed after the death of Otto Warmbier, an American tourist, in June after 17 months in North Korean custody. Two Korean Americans affiliated with PUST, as well as a businessman, are currently being detained in North Korea.

For Hammond and Maryknoll, the new rules could spell the end of an era, at least temporarily.

Maryknoll has had a mission in Korea since 1922. Back then, it was based in Pyongyang, the northern city that was such a center for religious activity that it was dubbed “the Jerusalem of the east.”

But after the civil war between the Koreas broke out in 1950 — during which several Catholic priests were killed by communists in the North — the mission moved its base to the South.

It was shortly afterward, in 1960, that the newly ordained Hammond arrived at the southern port of Busan on his mission. Fifty-seven years later, he’s still here.

During these decades, the Catholic Church has flourished in South Korea, which has become the most Catholic country in Asia after the Philippines. North Korea, meanwhile, has been run by a family of dictators that bans outside religions, viewing them as an existential threat to its personality cult.

But when a devastating famine arrived in the mid-1990s, North Korea allowed outside organizations, including religious ones, in to help with the humanitarian crisis.

Hammond first went to North Korea in 1995 to assist with the famine relief. “I never felt that going there was extraordinary because Maryknoll had worked in the North before the war,” he said at the Fathers and Brothers mission in Seoul.

[ Aid workers, Korean Americans voice concern about new North Korea travel rules ]

He then became involved with the ­Eugene Bell Foundation, an American-run organization that has treated more than a quarter-million tuberculosis patients in North Korea. It is run by Stephen Linton, also Philadelphia-born, who comes from a line of Southern Presbyterian missionaries who first arrived in Korea in 1895.

A decade ago, the foundation began focusing on multi-drug-resistant tuberculosis, a particularly pernicious form of infection that does not respond to standard TB medication. This requires an 18-month course of treatment; about three-quarters of treated North Koreans recover.

Hammond’s role with the foundation, he said prosaically, is “sputum security.”

The priest accustomed to giving cups of wine for Communion instead gives empty cups to patients, into which they provide samples. Those are analyzed to determine the six months’ worth of medicine and dietary supplements each patient receives.

Hammond cannot spread the word of God while he is in North Korea. Nor can Linton, nor the Christians associated with PUST, which is run by Korean American missionaries. Doing so would jeopardize their humanitarian efforts there.

But Hammond said he hopes his actions speak for themselves.

“In the early church, they didn’t have crucifixes or Roman collars or Bibles, but people knew they were Christian because they treated people with kindness,” Hammond said.

The North Koreans he helps don’t call him “Father” in the Catholic sense. Instead, they call him “Grandfather,” the Korean term of address for elderly men regardless of relation.

[ After Otto Warmbier’s death, tourism to North Korea comes under scrutiny ]

When Pope Francis visited South Korea in 2014, he praised Hammond for his “wonderful work” in North Korea, the priest recalled.

Earlier this month, Hammond received the Gaudium et Spes Award from the Knights of Columbus, the largest lay group in the Catholic Church.

The award — first given in 1992, to Mother Teresa — was presented to Hammond for his “heroic” work in North Korea. At the ceremony, Archbishop William Lori of Baltimore said Hammond’s mission was the manifestation of mercy: “Visiting the sick, comforting the afflicted, and feeding the hungry in body and soul.”

Hammond hopes to use the $100,000 award money to build new facilities in North Korea to house terminal patients.

“I want to build some patient rooms for the 20 percent of people who are not cured so they are able to die with dignity,” he said. “Also, we don’t want them to go back to their families and spread the disease.”

But international sanctions now make it very difficult to export any goods into North Korea, whether or not they’re prohibited. The Eugene Bell Foundation had difficulties getting its medicines out of South Korea last year for this reason.

Now, Hammond is waiting to hear whether he will be allowed to go back to North Korea and continue his work.

“Pope Francis wants us to go to the periphery,” he said, characterizing North Korea as the definition of peripheral and his work as the essence of Catholic — and American — values. “If you have any belief about anything, you know that if people are suffering, we should be helping them.”

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