Senate Republican leader Mitch McConnell, who had polio as a child, says any of President-elect Donald Trump’s nominees seeking Senate confirmation should “steer clear” of efforts to discredit the polio vaccine.

“Efforts to undermine public confidence in proven cures are not just uninformed — they’re dangerous,” McConnell said in a statement Friday. “Anyone seeking the Senate’s consent to serve in the incoming Administration would do well to steer clear of even the appearance of association with such efforts.”

The 82-year-old lawmaker’s statement appeared to be directed at Trump’s pick for health secretary, Robert F. Kennedy Jr., after a report that one of his advisers filed a petition to revoke approval for the polio vaccine in 2022. That vaccine is widely considered to have halted the disease in most parts of the world.