The lawyer helping Robert F. Kennedy Jr. pick federal health officials for the incoming Trump administration has petitioned the government to revoke its approval of the polio vaccine, which for decades has protected millions of people from a virus that can cause paralysis or death.

That campaign is just one front in the war that the lawyer, Aaron Siri, is waging against vaccines of all kinds.

Mr. Siri has also filed a petition seeking to pause the distribution of 13 other vaccines; challenged, and in some cases quashed, Covid vaccine mandates around the country; sued federal agencies for the disclosure of records related to vaccine approvals; and subjected prominent vaccine scientists to grueling videotaped depositions.