President Barack Obama boards Air Force One in Mexico City. The White House issued a health advisory outlining protective measures for anyone on the trip. W.H. issues advisory after Mexico trip

The White House has issued a health advisory outlining "protective measures" for anyone who traveled on President Barack Obama’s trip to Mexico after a member of the U.S. delegation came down with flu-like symptoms – and tests on his family showed they’re probably infected with the swine flu.

The individual – an advance security staffer for Energy Secretary Steven Chu –appears to have spread the flu to his wife, son and nephew. All three have tested probable for swine flu, White House Press Secretary Robert Gibbs said Thursday.


Gibbs, who did not name the security aide, said he did not work closely with Obama, didn’t fly on Air Force One and is back at work at the Energy Department.

But the staffer was at a working dinner Obama attended with Mexican officials April 16. The aide “was asked specifically if he ever came within six feet of the president, and the answer to that was 'No,' " Gibbs said.

“The president has not experienced any symptoms,” Gibbs said. He said Obama and other aides are “highly, highly, highly unlikely” to develop such symptoms now because of the time that has passed since Obama’s visit on April 16 and 17 and the relatively short incubation period for the flu virus, known as H1N1.

The disclosure of the likely flu case in the president’s entourage was startling because Gibbs said earlier this week that White House physicians believed the flu had posed no risk at all to Obama when he visited Mexico. “The doctors have informed me… that the President's health was never in any danger,” Gibbs said Monday.

Also on Monday, Gibbs had said no one traveling with the president “in either governmental or press capacity has shown any symptoms that would denote cause for any concern."

Gibbs said Thursday that Chu’s aide developed a fever while in Mexico and that several of the aide’s relatives subsequently fell ill with flu-like symptoms. The aide has not tested positive for swine flu, probably because so much time has elapsed, but tests on his three relatives came back as “probable” cases on Tuesday, Gibbs said.

The man flew back to Washington on a commercial United Airlines flight that landed at Dulles International Airport on April 18, Gibbs said.

Gibbs said Secretary Chu has shown no flu-like symptoms and has no plans to be tested for the virus.

Gibbs said a White House physician reported that about 10 staffers who traveled to Mexico visited him. But Gibbs said, “None of those people, however, came back with any positive tests.”

The press secretary said officials don’t expect any more cases related to the trip because of the time that has passed.

The White House advisory echoes the advice of the Centers for Disease Control – and even the president himself at Wednesday’s news conference – including urging workers to stay home if they suspect they have the virus. But the advisory also paints that advice as a way to make sure the White House can keep functioning, no matter how serious a global flu outbreak gets.

“Limiting influenza exposure within the buildings at the White House Complex will allow normal operations to continue, even if the world-wide influenza outbreak becomes more widespread,” the advisory reads.