Health Secretary Robert F. Kennedy Jr. fired the co-chairs of the U.S. Preventive Services Task Force last week. Why it matters: The move could open the task force up to more political influence. It comes as the administration prepares to vet new applicants to the committee, a process in which the chairs would typically be involved. The expert panel recommends which health services insurers must cover at no cost to patients under the Affordable Care Act. State of play: Kennedy sent letters da