President Trump on Sunday night said that the government would reassess the recommended period for keeping businesses shut and millions of workers at home after this week, amid millions of job losses caused by the efforts to contain the spread of the novel coronavirus.

“WE CANNOT LET THE CURE BE WORSE THAN THE PROBLEM ITSELF,” Mr. Trump tweeted in all capital letters shortly before midnight. “AT THE END OF THE 15 DAY PERIOD, WE WILL MAKE A DECISION AS TO WHICH WAY WE WANT TO GO!”

Officials have said that the initial 15-day period for social distancing — limiting close contact between people by banning gatherings, closing schools and offices, encouraging remote work and urging people to maintain a six-foot distance from one another — is vital to slowing the spread of the virus, for which more than 30,000 people in the United States have tested positive. The 15-day period would end Monday.

Dr. Anthony Fauci, an infectious diseases expert and a member of the White House coronavirus task force, has said in interviews that he believed that it would take several more weeks until people can start going about their lives in a more normal fashion. Other infectious disease experts suggest even harsher measures than social distancing are required to truly beat back the outbreaks in the United States.