These kinds of provocations will be familiar to fans and critics of Mr. Savage, who was once was barred from entering Britain after making inflammatory comments about Islam, including calling the Quran a “book of hate.”

In a series of interviews over the phone and on Skype as he recorded his radio show from a home studio overlooking San Francisco Bay, Mr. Savage, who is 78, echoed his conservative colleagues on some aspects of the virus. He has sharply attacked the federal government’s leading infectious disease expert, Dr. Anthony S. Fauci, dismissing him as “a grandstander” and “a showman.” He criticized sweeping quarantine measures and lockdowns as a threat to individual liberty, and called for them to be eased in places with lower infection rates, siding with the protesters who have gathered in state capitals across the country in recent days in a show of opposition.

He said he had pressed this point personally over email with Gov. Gavin Newsom of California, whom he knows socially through his son, the billionaire founder of Rockstar Energy Drink, Russell Weiner. Mr. Savage has also made his case on selectively lifting quarantine orders directly to the White House, which announced last month that it would nominate him to the board of the Presidio Trust, the oversight body for San Francisco’s famed national park. (The announcement was easy to overlook because it listed Mr. Savage by his legal name, Michael A. Weiner.)

Mr. Savage’s coronavirus crusade is partly a reflection of his training as a scientist. He has a Ph.D. from the University of California, Berkeley, in nutritional ethnomedicine, a field that examines how various cultures and ethnicities use natural products for health purposes. As part of his training, he studied epidemiology. He is a germaphobe and has a survivalist streak. One of the houses he owns in Marin County has its own reservoir.

But his persistence on the issue is also a reaction to his own recent death scare. The heart attack he had in December made the life-and-death nature of a pandemic personal. “I would like to believe that God has kept me here for this reason,” he said, calling this “the defining moment of our lives.”

At one point he turned to his producer, Jim Verdi, and asked, “When was I this wound up?”

“Never,” Mr. Verdi replied.

Mr. Savage’s wife, Janet Weiner, said in an interview that she had noticed more compassion in her husband since his heart attack. And she sees him taking on responsibility for waking people up to what parts of American conservatism, especially in the media, have become. “This culty hero worship of the uneducated, it’s very depressing,” she said. “It makes me ashamed to be a conservative,” she added, before stopping herself. “I don’t want to identify with the conservative movement anymore.”