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President Donald Trump on Wednesday tried to ease growing fears over the spreading coronavirus, saying at the White House that his administration has the situation under control and is "ready to adapt" if the virus spreads.

"Because of all we've done, the risk to the American people remains very low," Trump said. "We're ready to adapt and ready to do whatever we have to as the disease spreads, if it spreads.

"We're very, very ready for this," Trump said, adding that only 15 people had contracted the virus in the U.S. and that all were expected to recover.

Trump, speaking from the Brady Briefing Room, said he was putting Vice President Mike Pence in charge of his administration's response to the potential pandemic. Trump, however, rejected that he had made Pence a "czar" for the response to the virus.

Pence, speaking after Trump, reiterated that the "threat to the American public remains low" and said, "We will continue to bring the full resources of the federal government ... to see to the health and well-being and to the effective response to the coronavirus in the United States of America."

Trump — who this week announced a $2.5 billion plan to help combat the illness — said at the briefing, "We're going to spend whatever is appropriate."

Following the remarks of Trump and Pence, several senior officials from the National Institutes of Health and the Centers for Disease Control and Prevention spoke — and many didn't paint quite as rosy a picture. One NIH official said a potential coronavirus vaccine was still at least a year away.

The president's address came amid a tumbling stock market and grave criticism from Democrats who say his handling of the outbreak has been inadequate. It also came just a day after the CDC warned that it was only a matter of time before the illness, known as COVID-19, will spread across communities in the United States.

Coronavirus fears have spooked financial markets, which fell for the third straight day Wednesday. The Dow Jones Industrial Average fell more than 100 points Wednesday, nearly 900 points Tuesday and more than 1,000 points Monday.

And on Tuesday night, Democratic presidential candidates took turns bashing Trump for his administration's response. Sen. Bernie Sanders, I-Vt., the front-runner, mocked Trump's claims that the coronavirus is "under control."

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On Wednesday, Trump acknowledged that the markets had fallen because of coronavirus fears, but he added that he believed there was a second reason: the Democratic presidential candidates debating.

"I think they're very upset when they look at the Democrat candidates standing on the stage making fools out of themselves," Trump said when asked whether he agreed that markets were falling because of the virus.

Measures to contain the virus in the U.S. so far have involved restricting travel to and from China — the center of the outbreak — and isolating identified cases.

Full coverage of the coronavirus outbreak

Trump on Wednesday called those efforts "some very good early decisions" and indicated that he would consider restricting travel to South Korea and other countries "at the right time."

Until Wednesday, Trump had appeared to downplay concerns over the situation while playing up his administration's response to it.

Upon returning from a trip to India, Trump tweeted Wednesday that media outlets were "doing everything possible to make the Caronavirus look as bad as possible, including panicking markets, if possible," misspelling the name of the virus. He then criticized the pushback from Democrats on the administration's response to the outbreak and added, "USA in great shape!"

Earlier, Trump said at a new conference in India that the situation is "very well under control in our country."

The comments stood in stark contrast to a warning issued Tuesday by the CDC that a spread of COVID-19 inside the U.S. was inevitable and that "this might be bad."

Federal health officials added Tuesday that they are preparing for a potential pandemic. CDC officials said the virus could disrupt daily lives, including closing schools, forcing people to work from home and delaying elective medical procedures.

Trump, asked Wednesday whether schools should prepare for a spread of the virus, replied that "every aspect of our society" should be prepared. He added that he doesn't think it would come to that but that people should be prepared "just in case."

But he also vacillated at various points during his news conference between agreeing with and rejecting the stark warnings of a broader potential outbreak issued by government public health experts.

Responding to a question about the likelihood of a U.S. outbreak, he said, "I don't think it's inevitable.

"It probably will. It possibly will," he continued. "It could be at a very small level, or it could be at a larger level."

At another point, Trump said, "Nothing is inevitable."

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Some allies of the president, including conservative commentator Rush Limbaugh, have suggested that the CDC has exaggerated the threat to harm Trump politically. Trump, however, rejected the theory Wednesday when asked about it, and he praised the health agency and its employees.

In less than a month since the virus was officially declared a public health emergency, the number of confirmed cases globally has risen to more than 81,000, with the virus quickly spreading throughout Europe, hitting Italy the hardest hit so far with 300 confirmed cases in recent days.

The White House, however, could find itself hobbled in its response by cuts to programs over the past three years designed to act in just such a scenario. The White House has reduced the budget for the CDC and eliminated several key positions focused on responding to a pandemic, including having a CDC staffer in China working with disease detectives to quickly identify and contain new pathogens, according to Dr. Tom Frieden, the head of the CDC during the Obama administration.

The White House this week sent Congress a budget plan for $2.5 billion that would provide funds to speed vaccine development and production and stockpile protective equipment — funding that Democrats have called inadequate.