“My sole motivation for weighing in is to promote good public health awareness to do everything within our means to limit human loss or suffering,” Bossert said in an interview Thursday.

Indeed, the advice proved prescient. The virus has now landed on American shores and is infiltrating communities across the country. Theaters are shuttered, sporting events have ground to a halt, travel has slowed to a crawl. Offices are closed and officials are asking people to stay home. Around the world, financial markets are trembling.

And many health experts have said the situation has grown dire because the Trump administration didn’t heed these warnings.

The ominous message coming from former administration officials often stood in contrast to the upbeat White House narrative. As people like Bossert and Gottlieb pushed for the administration and public to recognize the virus’s disruptive potential, those immediately around the president publicly echoed Trump’s refrain that everything would soon return to normal. The disconnect is perhaps an example of the evolution of Trump’s administration — dissenting voices have fallen away in favor of those more willing to toe the Trump line.

A former administration official who worked with Gottlieb said the ex-FDA chief “saw pretty early on that people weren’t taking this seriously. And I can’t say if he was talking about the administration or the public at large, but he was trying to sound the alarm.”

On Twitter and TV, Gottlieb, Bossert and Cohn, among others, struck an urgent tone, while the president insisted the virus was “very much under control in the USA,” even predicting in late February that the number of cases would be close to zero “within a couple of days” and falsely claiming that a vaccine would soon arrive. As of Thursday, the number of cases had sailed past 1,000 and a vaccine remains at least a year away.