(CNN) New York, New Jersey and Connecticut have been placed under a 14-day travel advisory in the latest effort by United States officials to slow down the rapid spread of the deadly coronavirus.

More than 121,000 coronavirus cases have been reported in the US and more than half are in those states, according to CNN's tally of cases reported by health officials.

The US Centers for Disease Control and Prevention announced the new travel advisory Saturday night, urging people in those states to "refrain from non-essential domestic travel" after President Donald Trump announced on Twitter he had asked for it.

The CDC said this advisory does not apply to employees of critical infrastructure industries, including but not limited to trucking, public health professionals, financial services and food supply.

Trump also said a quarantine would not be necessary in those states. Earlier on Saturday, Trump tweeted that he was considering a two-week quarantine due to the pandemic, even though the governors of New York Connecticut and New Jersey were unaware of the possibility.

In an interview with CNN's Ana Cabrera Saturday evening, New York Gov. Andrew Cuomo said a quarantine "would be chaos and mayhem."

"It's totally opposite everything he's been saying. I don't think it is plausible. I don't think it is legal."

In the past days, federal and state authorities have been scrambling to slow down the spread of the deadly virus. The US surpassed Italy and China this week to become the country with the most coronavirus cases in the world

At least 121,285 people in the US have contracted the virus since the first case was reported in late January. The death toll has reached 2,043, doubling in the last two days.

Developments from around the country

An infant dies in Illinois: State health officials reported the death of an infant under the age of one who had tested positive for the coronavirus -- believed to be the youngest person to have in the United States. Illinois Department of Public Health Director Dr. Ngozi Ezike said a "full investigation is underway to determine the cause of death." State health officials reported the death of an infant under the age of one who had tested positive for the coronavirus -- believed to be the youngest person to have died with the virus in the United States. Illinois Department of Public Health Director Dr. Ngozi Ezike said a "full investigation is underway to determine the cause of death."

Trump approved four more emergency hospitals in New York: The facilities will be in Brooklyn, Queens, Staten Island and the Bronx, Cuomo announced Saturday, and provide 4,000 beds. Additionally, a temporary overflow hospital with 1,000 beds will open at Manhattan's Javits Convention Center on Monday, the governor said. The The facilities will be in Brooklyn, Queens, Staten Island and the Bronx, Cuomo announced Saturday, and provide 4,000 beds. Additionally, a temporary overflow hospital with 1,000 beds will open at Manhattan's Javits Convention Center on Monday, the governor said. The USNS Comfort is set to arrive in New York City the same day, providing another 1,000 beds.

State officials believe the state will need 140,000 beds when it reaches the apex of the pandemic in an estimated 14 to 21 days, Cuomo said

At least 215,000,000 Americans urged to stay home: Millions of Americans are under Millions of Americans are under various stay at home or shelter in place orders as of Saturday evening, according to a CNN count based on census data.

A 15-minute test is approved: On Friday, the On Friday, the FDA approved a coronavirus test that can provide results in less than 15 minutes, using the same technology that powers some rapid flu tests.

Pandemic will hit these states hard, top US doctor says

New hot spots have emerged across the country as case numbers escalate, including Detroit, Chicago and New Orleans, US Surgeon General Dr. Jerome Adams told "CBS This Morning" on Friday.

In Chicago, hospitals and health officials have begun preparing for a surge in patients after Mayor Lori Lightfoot said the city could see more than 40,000 hospitalizations in the next week, CNN affiliate WLS reported.

One registered ICU nurse with University of Chicago Medicine, who asked not to be named for fear of reprisal, told CNN that she's afraid of what the ICU will look like in another week as cases rise.

"The number of Covid patients we are getting is rapidly increasing every day," she said, "and all of us collectively worry about what will happen as it gets worse if this is where we are starting."

University of Chicago Medicine officials did not immediately respond to CNN's request for comment.

In Louisiana, where deaths surged by more than 40% in a single day this week and continue to jump daily, hospitals are already working under stress.

"This is going to be the disaster that defines our generation," said Collin Arnold, director of the city's Office of Homeland Security and Emergency Preparedness.

In Los Angeles County, cases more than tripled in six days , and one official says numbers will keep going up. Health Director Barbara Ferrer says she expects to see case counts in Los Angeles double every four days for the next two to three weeks.

"No matter where you are, this is coming to you," Los Angeles Mayor Eric Garcetti said Thursday. "Take all the measures you can now to make sure people are home."

100,000 ventilators in 100 days

More than 225 million Americans as of Monday will be under orders to stay inside to help combat the virus.

To support a struggling economy, as thousands of businesses have shut down amid the outbreak and workers are staying home, President Donald Trump on Friday signed the largest emergency aid package in the country's history.

Some of its key elements include sending checks directly to individuals and families, a major expansion of unemployment benefits, money for hard-hit hospitals and health care providers, financial assistance for small businesses and $500 billion in loans for distressed companies.

State leaders have also urged him to respond to a looming shortage of medical supplies. The administration will facilitate the production or acquisition of "100,000 additional units" of ventilators through other means over a 100-day period, Trump said.

"We are manufacturing a lot of them (ventilators) now, we are accumulating a lot. We are taking a lot through the act," Trump said, referring to the Defense Production Act, which he invoked Friday.

"Maybe we won't even need the full activation," he said. "We will find out, but we need the ventilators."