Officials do not know if the spread of the virus will be mild or severe, she added, but Americans should prepare for it to disrupt their daily lives.
"We are asking the American public to prepare for the expectation that this might be bad," Messonnier told The New York Times.
Schools are recommended to consider dividing classrooms into smaller groups or use "internet-based teleschooling" to limit person-to-person contact among students, according to The Times.
When it comes to businesses, the official advised for in-person meetings to be replaced by telephone conferences or other “teleworking” options, according to The Times.
»MORE: CDC issues Level 3 travel advisory for South Korea
On Monday night, President Donald Trump requested $2.5 billion that he said will prepare the nation in case of a U.S. outbreak, as well as help other nations unprepared to handle the threat.
Earlier Monday, the CDC confirmed 53 cases of coronavirus in the U.S. The new numbers include 36 recent evacuees from the Diamond Princess cruise ship. The number of stateside cases remains at 14.
»MORE: CDC confirms 53 cases of coronavirus in U.S.
The White House budget office said the funding would be used for vaccine development, treatment and protective equipment, but the amount of the request was quickly slammed by Democrats as insufficient. The budget request came as coronavirus fears were credited with Monday’s 1,000-plus-point drop in the Dow Jones industrial average.
»MORE: Dow plunges more than 1,000 points over coronavirus fears
The rapid spread of the virus and threat to the global economy has rocked financial markets, but Trump said he thinks China is getting the epidemic under control.
The funding request was released Monday evening and came as key government accounts were running low. The Department of Health and Human Services had already tapped into an emergency infectious disease rapid response fund and was seeking to transfer more than $130 million from other HHS accounts to combat the virus but is pressing for more.
»COMPLETE COVERAGE: CORONAVIRUS
On Tuesday, U.S. Health and Human Services Secretary Alex Azar said the U.S.’ stockpile of medical ventilators and masks is not enough for a COVID-19 outbreak.
South Korea is now on its highest alert for infectious diseases after cases there spiked. Italy reported a fifth person had died amid a sharp rise in cases, and a dozen towns in the northern part of that country are under quarantine.
The nation now has the biggest outbreak in Europe, prompting officials to cancel Venice’s famed Carnival, along with soccer matches and other public gatherings. In Iran, the virus reportedly has killed 50 in the city of Qom. Iraq confirmed the first case there Monday.