RFK Jr. is a high-profile face of vaccine hesitancy, but people's vaccine concerns fall on a much broader spectrum.

This story is part of MIT Technology Review’s "America Undone” series, examining how the foundations of US success in science and innovation are currently under threat. You can read the rest here.

This week, Robert F. Kennedy Jr., President Donald Trump’s pick to lead the US’s health agencies, has been facing questions from senators as part of his confirmation hearing for the role. So far, it’s been a dramatic watch, with plenty of fiery exchanges, screams from audience members, and damaging revelations.

There’s also been a lot of discussion about vaccines. Kennedy has long been a vocal critic of vaccines. He has spread misinformation about the effects of vaccines. He’s petitioned the government to revoke the approval of vaccines. He’s sued pharmaceutical companies that make vaccines.

Widespread distrust of our public health system is reviving long-debunked ideas on HIV and AIDS—and energizing a broad movement that questions the foundations of disease prevention.