WASHINGTON/NEW YORK (Reuters) - The United States and Canada closed their shared border to “non-essential traffic” on Wednesday to curb transmission of the coronavirus as U.S. President Donald Trump moved to bolster medical equipment supplies and the outbreak struck Capitol Hill.

Two members of the U.S. House representatives - Mario Diaz-Balart of Florida and Ben McAdams of Utah - said on Wednesday they had each tested positive for coronavirus, becoming the first lawmakers in Congress known to have become infected.

The implications for Capitol Hill were not immediately clear. The news came as the U.S. Senate passed legislation providing over $100 billion in emergency spending for free coronavirus testing, paid sick leave and expanded safety-net benefits.

Trump quickly signed the measure into law. Hours earlier, the Republican president said he would invoke the Defense Production Act to allow the government to accelerate production of medical equipment such as face masks and other protective gear during the health crisis.

“It’s a very tough situation here. You have to do things,” Trump said as he sought to escalate government action to address a public health crisis that he had initially made light of but has more recently likened to a war.

The defense statute, enacted in 1950 at the outset of the Korean War, empowers the president to expand industrial production of key materials or products for national security and other reasons.

Wall Street on Wednesday extended a four-week plunge in the face of deepening concerns over a fast-spreading and potentially lethal respiratory virus that has paralyzed large sectors of the U.S. economy and led to fears of a global recession.

VIRUS IN ALL 50 STATES

The Trump administration has been criticized for a slow initial response, with the United States now facing shortages of diagnostic testing kits and other essential medical supplies.

With cases of the highly contagious respiratory illness caused by the virus reported in all 50 states and the total number of known U.S. infections closing in on 8,000, millions of Americans are staying at home instead of commuting to work or going to school.

The U.S. death toll has climbed to at least 151.

New York, Washington state and California accounted for most of the cases, with the largest cluster of U.S. deaths from the illness - 62 - documented in the greater Seattle area.

California Governor Gavin Newsom said his state’s massive homeless population posed its own potential complications to the crisis. He cited computer models showing more than 60,000 people living without shelter in California could become ill with the coronavirus in the next eight weeks, badly straining the state’s healthcare system.

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Trump said two U.S. Navy hospital ships would be pressed into service, one to New York, the other on the West Coast. But U.S. defense officials said one of them, the Comfort, was undergoing maintenance in Virginia and it could take weeks before the vessel could head to New York Harbor.

Trump said closing the border with Canada for 30 days was by mutual consent and would not affect trade.

The two nations share one of the world’s largest trading relationships, and their economies are highly integrated.

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Canadian Prime Minister Justin Trudeau told reporters in Ottawa travelers could no longer cross the border for recreation and tourism.

“Our governments recognize it is critical that we preserve supply chains between both countries,” Trudeau added.

The U.S.-Mexico border would remain open, Trump said.

ECONOMIC STIMULUS

On top of the legislation signed into law on Wednesday, the Trump administration, as part of a $1 trillion stimulus and rescue proposal, asked Congress to approve $500 billion in cash payments to taxpayers in two rounds - on April 6 and May 18. It is also seeking $50 billion in loans to U.S. airlines, which have been pummeled by the pandemic, according to a document seen by Reuters.

Some Senate Republicans have called for delivering $1,000 checks to taxpayers, but Senate Democratic Leader Chuck Schumer said they should receive more.

It remained unclear whether the coronavirus diagnosis of two House members might hinder further congressional action.

Diaz-Balart, 58, a Republican, said he placed himself under self-quarantine in Washington on Friday after appearing on the House floor for a number of votes that day.

He said he developed a fever and headache on Saturday evening and got a positive test result shortly thereafter.

McAdams, a 45-year-old Democrat, said in a statement from West Jordan, Utah, that he had developed “mild cold-like” symptoms on Saturday evening after returning from Washington and isolated himself at home on Sunday.

He was tested for coronavirus at a local clinic on Tuesday after his symptoms worsened, and learned he had tested positive on Wednesday, McAdams said.

The House is due to return next week. House Speaker Nancy Pelosi’s office did not immediately respond to a request for comment.