Sen. John McCain is staying away from Washington, D.C., because of concerns about the deadly flu season, his daughter Meghan McCain says, in the first update on the senator's health since he left the nation's capital in mid-December.

"Part of the problem... is this deadly, crazy flu season," Meghan McCain, a panelist on "The View," told an interviewer on Politico's "Women Rule" podcast.

"His immune system is so down, everybody is worried about him getting the flu."

The podcast was posted Wednesday but was taped last Friday.

The 81-year-old McCain was diagnosed last July with an aggressive form of brain cancer that has a median survival rate of 14 months.

He flew back to Arizona before Christmas after being hospitalized at Walter Reed Medical Center for treatment of a viral infection.

McCain has been receiving physical therapy at his home near Sedona for the side effects of his cancer treatment.

"He tore both of his Achilles' tendons, and it's taken some time to get back to physical fighting form," Meghan McCain said. "It's a rough, rough, rough cancer."

"I'm not misrepresenting. He's doing really well right now."

After he left Washington in December, McCain's office had said he was planning to return to Washington in January.

His daughter offered this prediction: There's "a very high likelihood that he'll come back to D.C. at some point."

Meghan McCain moved up her planned wedding to last Thanksgiving because of her father's illness.

"You're living (brain) scan to scan," she said at the time.

She described her father as her biggest fan.

"I talk to him 10 times a day," she said. "He's always calling, he watches 'The View' every day. He does his therapy with his physical therapist during 'The View' times so it distracts him."

"Mentally, he's 100 percent there."