More generally, Mr. Shambaugh and others said, the federal government should spend whatever it takes to address the outbreak. Yields on government bonds have fallen to record lows in recent days, meaning the government can borrow money at little cost.

Cushion the blow.

The early stages of the coronavirus outbreak have had an acute impact on a relatively narrow set of industries and places. Airlines are warning of huge losses. Cruise operators are reeling. Restaurants are losing business in cities with substantial outbreaks, or where large events have been called off.

There are clear humanitarian reasons for helping the people who will lose jobs or income because of the outbreak. But there are also economic reasons. The clearest way for the virus to cause a recession is for the impact to spread beyond directly affected sectors, as people who lose jobs are forced to cut spending, leading to further job losses. Government programs could help prevent that.

“What a fiscal stimulus can do is try to erect firewalls as much as possible and try to make sure it doesn’t ripple out and affect the rest of the economy,” said Josh Bivens, director of research for the Economic Policy Institute, a progressive think tank.

Those programs could take various forms. Mr. Trump on Monday floated the idea of offering loans through the Small Business Administration to affected businesses, something that economists said could help minimize layoffs and keep companies from going out of business. The Federal Reserve on Monday also indicated it would allow banks to be flexible with customers if they fell behind on loan payments because of virus-related disruptions.

Adam S. Posen, president of the Peterson Institute for International Economics, likened the situation to the financial freeze-up after the collapse of Lehman Brothers in 2008. Back then, the Fed provided liquidity so that financial institutions could ride out the crisis. The federal government could play a similar role now.

“You got a bunch of people, small businesses — particularly in retail, transportation, hospitality, tourism — that are going to be temporarily disrupted and might go out of business and shed jobs, but that’s only because of this one-time shock,” Mr. Posen said. “So fiscal policy should be the bridge to get them over that shock.”