WASHINGTON — Over a week after President Donald Trump closed the U.S.-Canada border to non-essential travel due to coronavirus, crossings are down 90 percent — excluding trade traffic — along New York's northern frontier.

U.S. Customs and Border Patrol said in Buffalo, the busiest port of entry along the entire northern border, only about 500 passenger cars a day are crossing. Border officials did have to turn away some people looking to cross for recreational or tourism purposes in the days after the temporary closure took effect on March 21.

“We had some, but very few. The public has actually been really good," said Aaron Bowker, a supervisory Customs and Border Patrol officer. "We're not seeing very many."

Commercial traffic remains at normal levels across the border, said Bowker. Travel for trade reasons is considered essential under the border restrictions that are expected to remain in place until April 20.

People are also allowed to cross into the U.S. if they are health care workers, U.S. citizens or lawful permanent residents, Bowker said.

Rep. Elise Stefanik, R-Schuylerville, whose district lines the U.S.-Canada border, said she has heard of no problems with essential medical personnel crossing the border.

"That has been working well," she said. "I am in close touch, including texts, with hospital CEOs, and I have not had any particular issues with members of their work force."

While trade can continue across the border, ongoing restrictions may create challenges for cross-border supply chains and other commerce, Stefanik said.

"There is going to be significant economic challenges because we are so closely tied into the supply chain across the border," she said. "There’s a lot of small businesses and manufacturers that are facing challenging times.”

For the over 1,400 employees who work at the northern border in New York between Buffalo and Champlain, the coronavirus is a new and unusual obstacle to their work.

"Typically we can see our threats," said Bowker. "We have our frontline personnel out in the lanes and they interview every person that comes into the United States, whether they are a U.S. citizen or a foreign national. They're able to visibly identify certain threats, say for example, drug smuggling or weapon smuggling or currency smuggling. They're able to talk to people about possible illegal immigration. This is one of those things, you can't see it but it's dangerous."

U.S. Customs do not conduct medical screenings at the border, but will refer people to the Centers for Disease Control and Prevention if they display symptoms of coronavirus or have recently traveled from places that have severe outbreaks.

Customs staff wear personal protective equipment, like masks and gloves, if they must conduct inspections that force them to break distancing protocols, Bowker said. Around the country, this equipment is in short supply.

“We have enough right now to conduct operations,” Bowker said. "We have more coming.”

At least one Customs official has contracted coronavirus, according to the Buffalo News.

Senate Democratic Leader Charles E. Schumer and Sen. Kirsten Gillibrand, D-N.Y., both signed a letter to Trump last week with senators representing other northern border states requesting he consider the effects of border restrictions on medical supply chains, families and businesses with any future limitations.

"With more cases of coronavirus being diagnosed in New York’s border communities each day it’s imperative that the proper supplies, staff, and assistance that New Yorkers desperately need don’t get interrupted,” Schumer said.