Always aware of the markets, Trump was careful to avoid dire language as he talked about the economy, which he and congressional Republicans have routinely cited as a major accomplishment as they campaign for reelection.

“This is not a financial crisis. This is just a temporary moment of time that we will overcome as a nation and as a world,” Trump said, adding that the U.S. economy is well positioned to withstand the impacts of the virus because “our banks and financial institutions are fully capitalized and incredibly strong.”

Yet anxious investors were unmoved, as Dow futures fell after Trump's speech.

Overall, Trump did adopt a more solemn tone during his address, a change for a president who, as recently as Monday, compared the rapidly spreading virus to the common flu and tweeted that “nothing is shut down, life and the economy go on.”

The comparison to the flu was the latest in a series of inaccurate comments Trump has made about the virus as the number of confirmed U.S. cases has climbed over 1,000. Often, his public statements have contradicted top U.S. officials and Cabinet secretaries who have encouraged Americans — particularly older adults and those with chronic health conditions — to take the outbreak more seriously.

On Wednesday, Trump said all elderly individuals should cancel “nonessential travel in crowded areas” to reduce their risk of exposure to the virus.

“Every community faces different risks and it is critical for you to follow the guidelines of your local officials,” he said.

The president’s warning came hours after two U.S. officials testified on Capitol Hill that the worst is yet to come, and suggested that Americans should brace for further disruptions to their daily lives such as school closures, travel bans and cancellations of large gatherings.

In two surprising developments Wednesday night, the National Basketball Association suspended all games until further notice after one player tested positive for the coronavirus, and actor Tom Hanks and his wife, Rita Wilson, announced they had both contracted the virus.

And the virus appeared to grip the nation’s capital ever more tightly. A staffer in Democratic Sen. Maria Cantwell's D.C. office contracted coronavirus, marking the first known case on Capitol Hill. And at the Justice Department, employees received notice that there was a potential case at the agency. Over at the White House, public tours of the building were canceled.

“We have got to assume it is going to get worse and worse and worse,” said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases and a member of the Trump administration’s coronavirus task force, at a congressional hearing earlier Wednesday.

Fauci’s testimony was validated hours later when the World Health Organization officially declared COVID-19 a global pandemic, triggering a swift decline in U.S. markets and prompting Trump to schedule his televised address.

In Europe, Italy has suffered the most with over 10,000 cases. The country suspended most of its commercial activity on Wednesday as it essentially asked its population to shelter in place. Elsewhere in Europe, France, Spain and Germany all have over 1,000 cases.

China remains the hardest hit, with over 80,000 cases and upwards of 3,000 deaths. South Korea and Iran have also seen massive outbreaks, and Trump placed travel restrictions on both countries.

Hours after the pandemic declaration, Trump announced his plans to address the nation about the deadly virus — a move that put some officials inside the administration on edge, given the president’s attention-grabbing comments so far.

One administration official suggested Trump could “kiss a second term goodbye” if he failed to strike a more serious tone about the coronavirus outbreak that has already infected several hundred Americans and could impact a significant chunk of the U.S. population, according to epidemiologists who have been closely tracking the virus.

Even before Trump addressed the nation, his decision to deliver an Oval Office address alerted aides and lawmakers to a possible change in his approach.

One White House official said the president’s concerns about containment and public safety rose significantly on Tuesday, when several elite colleges — including Harvard University and the Massachusetts Institute of Technology — announced that classes would be moved online and students should refrain from returning to campus at the conclusion of spring break.

News coverage of the nationwide quarantine in Italy, where the virus has continued to spread uncontrollably and overwhelmed the country’s health care system, also unnerved the president, the same official said.

As concerns about public safety and worsening economic conditions accelerated inside the West Wing on Wednesday, Trump tried to strike a positive tone on Twitter: “America is the Greatest Country in the world… together we are putting into policy a plan to prevent, detect, treat and create a vaccine against Coronavirus to save lives in America and the world. America will get it done!”