Dr. Deborah Birx, the White House coronavirus response coordinator, said models projecting the number of American deaths from coronavirus have dropped dramatically in recent days because Americans have drastically changed their behavior.

Birx said the US was doing "much better in many cases than several other countries, and we're trying to understand that."

"We believe that our health care delivery system in the United States is quite extraordinary," she said, but added that the models were based on "what America is doing."

"I think what has been so remarkable I think to those of us that have been in the science field for so long," Birx continued, "is how important behavioral change is, and how amazing Americans are at adapting to and following through on these behavioral changes."

The nation's top infectious disease expert, Dr. Anthony Fauci, later said the changing models proved that social distancing steps are working.

"We know that mitigation does work. The reason that we know it works, is the question that was asked about the numbers...why they came down with the projections," Fauci said. "What you do with data will always outstrip a model. You redo your models depending upon your data."

"Our data is telling us that mitigation is working," Fauci said. "Keep your foot on the accelerator, because that is what's going to get us through this."

Some context: As CNN previously reported, an influential model tracking the coronavirus pandemic in the United States now predicts that fewer people will die and fewer hospital beds will be needed compared to its estimates from last week.

As of Wednesday, the model predicted the virus will kill 60,000 people in the United States over the next four months. That's about 33,000 fewer deaths than the model estimated last Thursday.

While the US is still expected to face a shortage of about 16,000 hospital beds, it will need 168,000 fewer beds than previously expected, according to the new analysis.