“We’re not ready—we have to start with that,” Birx told the audience at Fortune’s Brainstorm Health conference in Marina del Rey, Calif. 

“In fact, I worry that we’ve drifted even farther back than where we were in 2019.”

The country wasn’t in a great place in 2019, either. Its pandemic preparedness plan “failed in the first week,” when those in charge didn’t consider that people infected with the virus could have it—and spread it—without symptoms, Birx said.

On March 2—the day she came on board at the White House under former President Donald Trump—“there were no tests,” she recalled. “The only tests that were being done were through a public health lab.”

Her third day on the job, she called a meeting of private sector health care leaders and told them: “We need tests within days. And they delivered.”

At Birx’s request, companies collaborated, lost profit when they sent supplies to safety net hospitals, rearranged their supply chains, “and dropped all pretense of competition and just helped,” she recalled.

“I think people in the federal government believe the private sector is not there to help,” she added. “But the private sector stepped in to develop and produce tests, vaccines, and monoclonal antibody treatments that have saved millions of American lives.

“To me, across the board, the private sector is really an unsung hero.”

The country’s pandemic preparedness plans will continue to fail, Birx noted, until the private sector is brought to the table. Every year, federal agencies gather for a pandemic preparedness exercise, and companies that inevitably step in and save the day aren’t there, because they’re not welcome, she said.

In her mind, it makes no sense.

“The group that saved Americans was the private sector,” she said. “To not have the private sector at the table makes certain that we’re not going to be prepared.”