The first American case of coronavirus unrelated to any travel or exposure to another patient has been confirmed in the U.S.

The Atlanta-based Centers for Disease Control and Prevention confirmed the COVID-19 infection on Wednesday.

“It’s possible this could be an instance of community spread of COVID-19, which would be the first time this has happened in the United States,” the CDC said. “Community spread means spread of an illness for which the source of infection is unknown.”

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The CDC also said the patient, who is in California, may have been exposed to a returned traveler who was infected.

President Donald Trump declared Wednesday the U.S. is “very, very ready” for whatever the coronavirus threat brings, and he put his vice president in charge of overseeing the nation’s response.

Vice President Mike Pence to lead response against coronavirus

Trump sought to minimize fears of the virus spreading widely across the U.S., saying, “I don’t think it’s inevitable.”

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“Our aggressive containment strategy here in the United States has been working and is responsible for the low levels of cases we have so far. However, we do expect more cases,” said Dr. Anne Schuchat, CDC’ principal deputy director.

U.S. Health and Human Services secretary Alex Azar said more cases in the U.S. are likely.

More than 81,000 cases of COVID-19, an illness characterized by fever and coughing and sometimes shortness of breath or pneumonia, have occurred since the new virus emerged in China.

The goal is to quickly identify coronavirus cases and take appropriate health action to reduce its spread and protect the general public.

The National Institutes of Health’s top infectious disease chief cautioned a vaccine won’t be ready for widespread use for a year or more — but said the virus might return, so researchers have to push ahead.

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NIH’s Dr. Anthony Fauci called it “quite conceivable” that the virus will “come back and recycle next year. In that case, we hope to have a vaccine.”

Trump said Vice President Mike Pence will work with CDC, NIH and other government agencies to coordinate the response.

In previous outbreaks, the White House has appointed a “czar” to pull together the different departments’ work.

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“We’re very, very ready for this, for anything,” even if it’s “a breakout of larger proportions,” Trump told a news conference.

On Capitol Hill, senior lawmakers called for a bipartisan spending package that would give federal, state and local officials more resources.

Trump had requested $2.5 billion to fight the virus; Senate Democratic leader Chuck Schumer of New York countered with an $8.5 billion proposal.

Trump told reporters he was open to spending “whatever’s appropriate.”

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Aides said the House measure is likely to be unveiled next week. Bipartisan “four corner” meetings — Democrats and Republicans in both the House and Senate — began Wednesday, a House Democratic aide said, with a bipartisan bill the goal.

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Trump has wondered aloud if Health and Human Services Secretary Alex Azar is the right person to lead the administration’s response. The White House had considered naming a virus czar but was not sure that was the right route, said a person familiar with the discussions.