More than 100 people have been refused entry from Canada into the United States as a result of coronavirus-related travel restrictions, according to officials in both countries.

Those refusals stem from new U.S. rules banning entry to anyone recently in coronavirus-affected China and Iran.

At least 70 Canadian citizens and 47 permanent residents of Canada had been denied entry into the U.S. through March 2 as a result of overseas travel to affected areas, Public Safety Canada told CBC News.

Such border woes underscore the potential disruption from a virus that has already rocked markets; stranded Canadians on cruise ships; and on Friday led Scotiabank to chop 0.4 percentage points from its global economic growth forecast for the year, to its lowest level since 2009.

Details about Canadians being blocked from the U.S. were first revealed during a congressional hearing Thursday in Washington by Ken Cuccinelli, acting director of U.S. Citizenship and Immigration Services.

He noted that U.S. restrictions apply at land borders in addition to air travel. As a result, he said, the land-travel rule has affected more people from Canada than anywhere else.

The issue initially came up when a border-state senator pressed Cuccinelli about what's being done to protect Americans from coronavirus.

Unlike Canada, which is screening travellers and quarantining the most at-risk ones, the U.S. is systematically banning entry to travellers from certain places.

During Thursday's hearing, Michigan Sen. Gary Peters noted his state houses several of the most active land crossings and he asked the administration official what precautions were being applied there.

The issue surfaced again later in the hearing, when Sen. Kamala Harris asked whether the administration was avoiding racially profiling Asian Americans amid coronavirus fears.

"Some people may find it ironic, but the largest excluded group are Canadians. It is Canadians who had traveled to China in the previous two weeks," Cuccinelli said.

"The next largest group were Chinese nationals."

U.S. border guards use two methods to screen passengers, he said: First, they examine travel data, and also ask questions about recent travel.

Another border-state senator warned that the U.S. cannot entirely seal off its border — because it would be devastating to the broader economy.

Wisconsin Republican Ron Johnson, the chair of the committee holding the hearing, concurred with Peters, a Michigan Democrat, that the goal of border restrictions is not to eliminate all threats — it's to slow the rate of transmission and buy time for the development of a vaccine.

"Just trying to create realistic expectations," Johnson said.

"If [the border] was hermetically sealed, we wouldn't have trade at the border. Overreacting here would be unbelievably costly."

Ken Cuccinelli, acting director for the U.S. Citizenship and Immigration Services, U.S. Department of Homeland Security, testifies on Capitol Hill in Washington in 2019. 'Some people may find it ironic, but the largest excluded group are Canadians. It is Canadians who had travelled to China in the previous two weeks,' Cuccinelli told U.S. lawmakers on Thursday. (Jose Luis Magana/The Associated Press)

In response to Harris's question about racial profiling, Cuccinelli concurred that ethnicity does not matter.

"There is without question no difference that this virus shows whether you're black, white, Asian, Hispanic, anything else," he said.

"[More] Canadians have been barred from the United States on the northern border than Chinese — 113 [Canadians] to 90 [Chinese] … because it was travel based. It wasn't that, 'You're Chinese.' It's that you have been in the hot zone in the [last] 14 days."

Canada's public safety minister was in Washington discussing coronavirus measures with colleagues at the Department of Homeland Security on Thursday.

Canadian minister discusses issue in Washington

Bill Blair told CBC News that he discussed the border issue with his U.S. counterpart, Chad Wolf, the acting U.S. secretary of homeland security.

He said some people denied entry at the U.S. border will be Canadian citizens, and some are people with other nationalities passing through Canada.

Blair said Canada prefers a more targeted approach, questioning and quarantining the most at-risk travellers.

But he said the U.S. has every right to make its own decision about how to handle its coronavirus response.

"We do respect sovereign countries. And the United States has undertaken this measure for people who have travelled from those areas — that they're just prohibiting their entry," Blair said in an interview in Washington.

"Canadians who have recently been in the affected areas, within the past 14 days, before they would be allowed entry into the United States they would be screened and if in fact they've been in those affected areas they would be prohibited from entering into the United States."