Ivanka Trump and Jared Kushner test negative for coronavirus as a slew of White House aides are screened after the president contracts the disease

• President Donald Trump and First Lady Melania Trump have contracted the coronavirus and are quarantining, the president tweeted around 1 a.m. on Friday.
• His daughter, Ivanka, and son-in-law, Jared Kushner, both of whom are senior White House advisors, were screened for the coronavirus and tested negative. So, too, did the president's youngest child, Barron.
• Multiple White House officials have been tested for the highly contagious disease after news emerged late Thursday that Hope Hicks, a senior aide to the president who traveled with him on Air Force One this week, had tested positive.

President Donald Trump's daughter, Ivanka, and his son-in-law, Jared Kushner, have tested negative for the coronavirus, White House spokesperson Carolina Hurley announced on Twitter on Friday.

News broke on Thursday that Hope Hicks, a senior aide to the president, had tested positive for the disease after traveling with him this week aboard Air Force One.

Initially, Trump tweeted that he and First Lady Melania Trump were awaiting their COVID-19 test results.

Two hours later, he tweeted that the pair had "tested positive," but it remains unclear when exactly they were exposed to the virus.

"We will begin our quarantine and recovery process immediately. We will get through this TOGETHER!" wrote Trump, who is said to be experiencing "mild symptoms" as is the first lady.

What followed was a flurry of Trump administration officials, including Vice President Mike Pence, White House Chief of Staff Mark Meadows, Secretary of State Mike Pompeo, and Attorney General William Barr, being screened for the highly contagious disease. So far, they have all tested negative.

Ivanka and Kushner, both senior White House advisors, accompanied Trump to the first presidential debate in Cleveland, Ohio, on Tuesday alongside others aides and family members. Donald, Jr., Eric, Ivanka, and Tiffany Trump did not wear masks, defying the event's rules and CDC guidelines.

Also on Friday, Stephanie Grisham, the first lady's chief of staff, announced that Barron Trump, too, has tested negative for COVID-19.

"All precautions are being taken to ensure he's kept safe and healthy," Grisham told USA TODAY.

The president has downplayed the threat of COVID-19 since it emerged in China late last year, telling the veteran journalist Bob Woodward that he did so to avoid causing a panic among the American public. He has also repeatedly called on the country's leaders to lift lockdown measures and reopen the economy. And the president's campaign rallies, as recently as this week, featured large crowds of people who aren't maintaining social distance or wearing face masks, despite expert advice to the contrary.

As of Friday, the United States is in the throes of the worst coronavirus outbreak on earth with more than 7.2 million cases and nearly 207,900 deaths.

The average incubation period for the virus is five days, according to epidemiologists at Johns Hopkins University.

Determining how long it takes for symptoms to emerge is "particularly relevant when you're thinking about how long you actually have to monitor people to make sure that they're not infected," Lauren Ancel Meyers, a professor of integrative biology at the University of Texas at Austin, previously told Business Insider.

This means, the first family will need to be closely watched because a negative test on Friday doesn't mean they can't still fall sick.