Juan Williams, a veteran Fox News personality who co-hosts the popular afternoon talk show “The Five,” tested positive for the coronavirus on Thursday and is isolating himself, two people who were briefed on his condition said.
Mr. Williams taped a live episode of “The Five” on Wednesday afternoon at Fox News’s Midtown Manhattan headquarters, appearing on the set with several of his co-hosts, including the popular conservative commentators Jesse Watters and Greg Gutfeld. The hosts, like guests on some other cable talk shows during the pandemic, sat about seven feet apart.
Mr. Williams left for vacation on Nov. 18 and returned to the Fox News studios on Monday; he was tested for the coronavirus shortly thereafter. The people familiar with his condition, who requested anonymity to share private discussions, said he received a positive result on Thursday afternoon.
He was absent from Thursday’s 5 p.m. episode of “The Five,” in which the other hosts appeared remotely.
Fox News declined to comment about Mr. Williams’s condition, citing employee privacy. But the network said in a statement that the hosts of “The Five” would broadcast from home studios “for the foreseeable future.”
“We will continue to take all necessary precautions to ensure the safety of our staff,” the statement said. It noted that the network regularly tested its on-air personalities and had mask mandates and daily health checks for all employees who entered its headquarters.
On a talk show where the opinions skew Trumpward, Mr. Williams is the liberal-leaning outlier who has often criticized President Trump’s handling of, among other matters, the coronavirus pandemic. On Wednesday’s program, Mr. Williams called Mr. Watters “shameful” for advancing Mr. Trump’s debunked theories about election fraud. (“Juan sounds nervous,” Mr. Watters riposted.)
In September, “The Five” was one of the most prominent television panel shows to return to in-studio broadcasts after an extended period when the hosts worked from home. (The show’s usual large desk was replaced with separate stools for the hosts.) Several stars of “The View” on ABC, for instance, continue to work remotely. “The Talk,” a panel show on CBS, also returned to the studio in September.
Mr. Williams was among a group of Fox News stars and executives who were potentially exposed to the virus at the first presidential debate in September in Cleveland, where Mr. Trump appeared onstage days before announcing he had contracted the virus.
Mr. Williams was exposed again in October after traveling back from the second presidential debate, in Nashville, with a Fox News employee who later tested positive for the virus.
At the time, the chief executive of Fox News Media, Suzanne Scott, told employees in a memo that the network would limit the number of staff members working in its Manhattan office.
Since returning from his vacation on Monday, Mr. Williams had also appeared on-set with his regular “Five” co-host Dana Perino and several guest panelists, including the anchors Sandra Smith and Dagen McDowell and the conservative pundit Katie Pavlich.
Other television news personalities who have tested positive for the virus include Brooke Baldwin and Chris Cuomo of CNN, Lesley Stahl of CBS, and George Stephanopoulos of ABC News. They have since recovered.
Ben Smith contributed reporting.