On Friday President Trump arrived at Walter Reed Medical Center, where he will stay for a "few days" as he recovers from COVID-19.
Some are asking why the president continued traveling, even after learning one of his closest aides, Hope Hicks, had tested positive and was symptomatic.
President Trump has been traveling all week and was seen getting out of Marine One in Washington, DC Thursday after a trip to Bedminster, where he attended an event at his golf club.
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Governor Phil Murphy is wishing the president well, but he is also urging anyone who attended the fundraiser to get tested.
"Tammy and I send our best wishes to President Trump and First Lady Melania Trump for a speedy and complete return to good health," he said in a statement. "If there is one thing we have learned in New Jersey over these months, it's that we pull together and support everyone fighting this virus. The contact-tracing process is underway. We urge everyone who attended yesterday's event in Bedminster to take full precautions, including self-quarantining and getting tested."
The Somerset County Health Department has begun contact tracing to determine the potential risk of exposure to attendees and staff.
The county has reached out to Trump National Golf Course with a request for lists of faculty staff, event participants, and other people to help identify those who may have come in close contact with individuals that tested positive.
It's recommending health control measures to identify close contacts based on its investigation.
Those in attendance, including comedian Joe Piscopo, said the president was energized and gave an enthusiastic speech before answering questions for an extended period of time.
They said everyone was tested before entering and given a mask, although Trump did not wear one.
Dr. Rich Roberts, of Lakewood, sat "directly across" from Trump and said the president was in "top spirits, full of fight and energy," in a video debriefing made before news broke of the positive test.
Another person who attended, Republican donor John Sette, told ABC News that President Trump was "100% normal. He took questions for an hour, an hour 15 minutes."
Hicks, a longtime member of Trump's inner circle, tested positive on Wednesday after showing symptoms. She has been with the president this week in Ohio for the debate and Minnesota for a campaign rally.
"She is among his closest aides," ABC News Correspondent Cecilia Vega said. "They were right next to each other in that small space, Marine One, the presidential helicopter, she is in the Oval Office all the time in direct contact with him. So just in terms of the logic of the way COVID spreads, it's not surprising that he caught it."
Trump's Bedminster event included a roundtable discussion, a photo line with the president, and a reception, according to a local New Jersey media report.
Highest tier tickets cost $250,000. For a photo with Trump and tickets to the reception, the price was $50,000.
"As usual, the event site was professionally cleaned and sanitized prior to the event," A Republican National Committee spokesperson told ABC News. "The White House Medical Unit and U.S. Secret Service evaluated all attendees in order for them to gain access to the event. Attendees tested negative for COVID-19 on the day of the event, completed a wellness questionnaire, and passed a temperature screening."
Video from the Facebook group Somerset County for Trump shows supporters gathered in close proximity outside his golf club Thursday with most not wearing masks.
Both President Trump and the First Lady have interacted with scores of people at high profile events across the country in the last week, often seen in close proximity, and seldom with a mask on.
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