For many Americans, the coronavirus pandemic started on the night of March 11.
News of a trio of events spread quickly across the United States: The actors Tom Hanks and his wife, Rita Wilson, announced that they had caught the virus, President Donald Trump addressed the nation and announced a ban on foreign nationals' entering the U.S. from many European countries, and the NBA indefinitely suspended its season.
Coronavirus concerns had penetrated the national consciousness before then, but the succession of events became a turning point in how the nation regarded the virus.
Almost seven months later, the news that Trump and first lady Melania Trump had contracted the virus has created a similar turning point at a time when coronavirus fatigue had caused concern among experts that the U.S. was no longer taking the pandemic seriously as a continuing health crisis.
It comes, however, in an environment in which the pandemic has been heavily politicized for months, leaving no guarantee that the president's situation will resonate as that night in March did.
"I think we're in uncharted territory," said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. "I think we might find, depending on how this unfolds over the next two to three weeks, we do get more of the public's understanding and support for responding to this pandemic. But this could just be a whole series of land mines going off. We don't know."
Coronavirus cases in the U.S. were already on the rise in recent weeks, with many states reporting outbreaks and some considering reintroducing restrictions on businesses. Dr. Anthony Fauci, the government's leading expert on infectious diseases, recently warned that the country was "not in a good place."
Beyond the numbers, coronavirus fatigue had already set in. A growing number of Americans said in a recent NBC News|SurveyMonkey poll that the U.S. was reopening too slowly and that they regarded the coronavirus as more of an economic crisis than a health crisis. U.S. search interest on Google steadily declined from spring to summer and into fall — and it spiked in the early morning hours Friday.
Even medical experts said they had seen fatigue in their ranks.
"I lead an organization of about 500 people, and we see it with our own staff," said Dr. Christopher Murray, a professor of health metrics sciences at the University of Washington. "It is tough for people to be at home and work and school from home and to manage all the challenges that the pandemic has imposed without all the usual social supports or diversions that make up people's lives."
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While the U.S. has yet to gain broad control over the virus, parts of the country had some success in pushing infection rates down in recent months. New York, one of the hardest-hit states in the spring, was able to lower its infection rates to the point that New York City instituted the return of limited indoor dining. Across the country, colleges and universities welcomed students back to campuses, and school districts worked to reopen schools.
The election campaign added political urgency to calls to reopen. At the first presidential debate Tuesday, Trump and Democratic nominee Joe Biden clashed over how and when schools and businesses should reopen.
"They think they're hurting us by keeping it closed. They're hurting people," Trump said. "And this guy will close down the whole country. He will destroy our country."
If the coronavirus pandemic had become background noise for some people, Trump's diagnosis made it unavoidable. Discussion of the president's situation blanketed news coverage Friday. By midday, Covid-19 was the top trending topic on Twitter by an extreme margin: 3.5 million tweets, compared to about 27,000 for the next closest story, about an assault on the actor Rick Moranis.
By late Friday afternoon, reports of a fever and an experimental antibody cocktail, as well as images of the president's helicopter waiting to take him to Walter Reed National Military Medical Center, added further urgency.
But it wasn't clear whether Trump's situation had immediately changed how the White House was conducting its business. When chief of staff Mark Meadows briefed reporters Friday morning, he did so without a mask, as did press secretary Kayleigh McEnany. When asked why he wasn't wearing one, Meadows said he'd been tested and was more than 6 feet away.
"If there's any concern there from a guidance standpoint, we have protocols in place," he said.
Covid-19 deniers seemed unmoved by the news of the president's positive test result. In dozens of conspiracy theory-focused Facebook groups monitored by NBC News, people doubled down on their extreme defiance against protective measures such as masks and social distancing.
Some Democrats said they hoped the news would be a turning point.
"I wish President Trump and the First Lady a speedy recovery," Rep. Frank Pallone, D-N.J., tweeted. "I hope this diagnosis serves as a wake-up call for everyone who refuses to listen to public health experts and scientists."
Dr. Howard Koh, a professor at the Harvard T.H. Chan School of Public Health, who was assistant secretary of health and human services in the administration of President Barack Obama, said he hoped the president's situation would persuade people to depoliticize the pandemic.
"I think, until now, so many have underappreciated the risks despite how long this has all gone on," Koh said. "Unfortunately, the president has contributed to that by downplaying the risks. It's time to put all that behind us and double down on the best scientific and public health guidance and move forward."