President Donald Trump, Vice President Mike Pence, and senior US health officials announced Saturday afternoon that the Trump administration will respond to a global increase in confirmed cases of the novel coronavirus by expanding its travel ban on Iran and issuing “do not travel” warnings to areas in Italy and South Korea most affected by viral outbreaks.

The announcement comes in the wake of the first US death due to the novel coronavirus in Washington state, where a woman in her 50s, described by the president Saturday as being “medically high-risk,” died from the virus overnight.

Under the new travel restrictions, no Iranians or non-Americans who have been to the country in the last 14 days will be allowed to enter the US, Pence said.

Iran has reported 593 cases of the coronavirus and 43 deaths — the largest number of deaths outside of mainland China. As of Saturday afternoon, Italy has 1,128 confirmed cases and South Korea has 3,150, according to data compiled by researchers at Johns Hopkins University.

Public health officials at the president’s press conference warned Americans to expect the number of diagnosed coronavirus cases in the US to increase but said the chance of catching the virus remains low. The majority of those who contract the virus — 75 to 80 percent, according to Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases — will experience it like a “bad flu or a cold.” Healthy people who do become infected by the virus should simply stay at home and treat their symptoms like they would a cold, said Secretary of Health and Human Services Alex Azar.

The other 15 to 20 percent, according to Fauci, may need “advanced medical care.”

“For the most part, the people who get in trouble and ultimately tragically would die from this are people who are elderly and or have underlying conditions,” Fauci said. “Heart disease, chronic lung disease, diabetes, obesity.”

The officials also stressed that Americans should not buy face masks. Amid concerns that a public rush to buy masks would create a shortage for health care workers and patients who have been diagnosed — those who experts say should have access to masks to stop the spread of the virus — the administration announced they’re making 40 million more masks available to health care workers and are contracting with 3M to commission 35 million more.

“This is an all-hands-on-deck effort,” Pence told reporters Saturday. “While the risk to Americans remain low, the president’s actions today with regard to Iran — with regard to Italy and South Korea and with regard to making medical supplies more available — I hope gives evidence to the fact that, at his direction, we’re going to continue to lean into this effort and put the health and safety of the American people first.”

Officials are not yet discouraging travel within the US, including to states where cases have been identified.

Trump also promised to meet “with the largest pharmaceutical companies in the world” Monday to discuss plans to develop a possible vaccine for the virus “very quickly,” though Fauci has said it will take a year to 18 months to make treatment widely available.

The first US cases of coronavirus “community spread” were discovered Friday

The Washington woman’s death comes following a Friday report of four new coronavirus cases in three US states: one in Oregon, one in California, and two in Washington.

These cases were, for the first time, a result of “community spread,” Fauci said Saturday. That means they did not arise after travel or contact with someone already diagnosed and may be a sign that the virus is spreading within communities.

“That really challenges us with something that we need to do and that we do very well,” Fauci said. Health authorities “would need to identify, isolate, and contact trace. That’s what’s going on in right here in the country.”

While the Trump administration offered its latest anti-coronavirus strategies Saturday, at the moment, the majority of cases of coronavirus are still outside the US. South Korean officials announced more than 800 new cases of Covid-19 — the disease caused by the novel coronavirus — Saturday, marking the biggest daily jump in infections in the country.

The first South Korean novel coronavirus case was just discovered six weeks ago, and since that time, the country has already suffered 17 deaths due to the virus. South Korean officials are calling the increase a “critical moment” in the virus’s spread and have warned people to practice “social distancing” for the next few days. South Korea has the second-highest number of confirmed cases worldwide behind China.

Overall, experts say US citizens should not panic, but that there are good ways to protect oneself. That includes, yes, washing your hands. But wearing a face mask isn’t helpful if you aren’t sick (although it’s a good idea to wear one if you are). And, if possible, experts have advised stocking up on a few weeks’ worth of supplies as well as making a plan for what you would do if you or your family were kept from school, daycare, or work.