In Coudersport, Pennsylvania, a town in a mountainous region an hour’s drive from the nearest Wal-Mart, Cole Memorial Hospital counts on two Jordanian physicians to keep its obstetrics unit open and is actively recruiting foreign specialists.

In Fargo, North Dakota, a gastroenterologist from Lebanon — who is among thousands of foreign physicians in the state — has risen to become vice president of the North Dakota Medical Association.

In Great Falls, Montana, 60 percent of the doctors who specialize in hospital care at Benefis Health System, which serves about 230,000 people in 15 counties, are foreign doctors on work visas.

Small-town America relies on a steady flow of doctors from around the world. But a recent decision by the government to alter the timetable for some visa applications is likely to delay the arrival of new foreign doctors, and is causing concern in the places that depend on them.

While the Trump administration is fighting for its temporary travel ban affecting six countries, the slowdown in the rural doctor pipeline shows how even a small change can ripple throughout the country.

In Montana, for example, where nine counties do not have a single physician, it means Benefis Health does not know when a Romanian doctor trained in kidney transplants will arrive. The health care company spent months recruiting the doctor and had been expecting her in July.

The procedural change regards temporary visas for skilled workers, known as H-1B visas. U.S. Citizenship and Immigration Services recently announced that it would temporarily suspend a “premium processing” option by which employers could pay an extra $1,225 to have H-1B applications approved in as little as two weeks, rather than several months.

Companies using that option, the government said, have effectively delayed visas for others that did not pay the extra fee.

A spokeswoman for the immigration agency, Arwen Consaul, said in a statement that the measure was necessary to “work down the existing backlogs due to the high volume of incoming petitions.”

The immigration agency said in a statement that applicants could still request an H-1B approval on an “expedited basis,” if they could prove there was an emergency or humanitarian justification.

Immigration lawyers said that it was extremely difficult to meet that standard, and that they doubted whether the agency could handle a flood of such requests.

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