O’Brien’s diagnosis marks the highest-ranking Trump administration official known to have tested positive. It is unclear when O’Brien last met with Trump. Their last public appearance together was more than two weeks ago during a visit to the United States Southern Command in Miami on July 10.
O’Brien, one of Trump’s top advisers, recently returned from Europe, where he and his top deputy met with officials from the United Kingdom, France, Germany and Italy.
A senior administration official told CNN that O’Brien has been working from home since last week. A family source said O’Brien was the last in the office last Thursday, when he abruptly left the White House.
Several members of the National Security Council staff told CNN that they were not informed that O’Brien tested positive and learned of the news from media reports.
The head of the National Security Council was accompanied on the trip to Europe by Secret Service agents, employees and multiple reporters. Multiple images posted on the trip showed O’Brien without practicing social distancing or wearing a mask.
As the pandemic spread, the President defended against wearing a mask or social distancing, and many of his top White House officials and employees did the same, saying it is not necessary because tests are done every day. O’Brien’s positive test underscores the unique challenges of keeping the virus away from the West Wing and the President’s immediate orbit.
Last week, administration officials were alerted that a cafeteria employee on the White House grounds had tested positive. Kimberly Guilfoyle, the girlfriend of the president’s son and the campaign’s chief fundraising officer, tested positive before a trip to Mt. Rushmore earlier this month. Multiple Secret Service agents and campaign staff tested positive after becoming infected as they prepared for the president’s campaign rally in Tulsa in June. Vice President Mike Pence’s communications assistant Katie Miller tested positive for coronavirus in May, and one of the president’s personal aides tested positive earlier that week.
O’Brien, Trump’s fourth national security adviser, was largely out of sight during the coronavirus pandemic. CNN previously reported that instead of helping lead the administration’s response, it delegated responsibilities to top attendees and even avoided coronavirus task force meetings.
Trump turned to O’Brien, a former lawyer and hostage negotiator, for the post in September 2019, a week after he fired John Bolton amid disagreements over foreign policy issues.
This story has been updated with additional developments on Monday.
