By ANNE FLAHERTY and MARIAM KHAN, ABC NEWS

(WASHINGTON) — The nation’s top health experts on Tuesday directly contradicted President Donald Trump’s suggestion that coronavirus testing should slow down, telling lawmakers that more tests — not fewer — are needed to curb the rate of COVID-19 infections.

In a hearing before the House Energy and Commerce Committee, the senior administration officials also warned that America remains gripped by the crisis and that the situation could grow worse by fall.

“A couple of days ago, there were 30,000 new infections. That’s very disturbing to me,” said Anthony Fauci, the top infectious disease expert at the National Institute of Health.

At issue is how aggressively state and local officials should be testing Americans for the highly contagious virus and whether the White House should be doing more to encourage Americans to stay home and wear masks.

Facing an election in November, Trump has been dismissive of outbreaks in some states and opted Tuesday to rally supporters at a megachurch in Arizona, where certain counties were experiencing large jumps in case numbers.

This weekend at a rally in Tulsa, Oklahoma, Trump prompted some head scratching when he told supporters that he urged his staff to slow down testing. His aides later suggested he was only joking. When asked Tuesday, he would only say, “I don’t kid.”

When asked at the hearing Tuesday, each of the four government witnesses said no one had ever asked them to try to slow testing, which would be difficult to do. Testing is conducted at the state and local level with mostly logistical support from the federal government.

The four witnesses also said slowing testing wouldn’t be a good idea. The U.S. has conducted nearly 22 million tests, at a rate of between 400,000 and 500,000 tests per day.

“Neither the president or the administration has suggested we do less testing to me. We are proceeding in the opposite,” said Adm. Brett Giroir, a senior Health and Human Services official who Trump hand-picked to coordinate federal testing efforts.

“My purpose in leading is to increase the number of testing,” Giroir later added. “The only way we will be able to understand who has the disease, who is infected and can pass it, and to contact tracing, is to test appropriately, smartly, and as many as we can.”

Joining Fauci and Giroir were Robert Redfield, director of the Centers for Disease Control and Prevention and Stephen Hahn, head of the U.S. Food and Drug Administration.

“I know for sure none of us have ever been told to slow down on testing. That is just a fact,” Fauci said.

Fauci also said that the next couple of weeks will be critical in addressing hotspots emerging in Florida, Texas, Arizona and other states.

“I have said multiple times publicly that we are still in the middle of the first wave,” he said. “Before you start talking about a second wave, what we’d like to do is get this outbreak under control.”

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