Why Young Adults Are Among the Biggest Barriers to Mass Immunity

Bridget Burke, 22, a college student in Michigan, said she was unsettled by rumors that Covid-19 vaccines could affect her reproductive health. Bryson Hardy, 19, a fiber optic cable splicer from Georgia, said he was not worried about contracting the virus and had no plans to get vaccinated. And Cinda Heard, 27, an in-home health care assistant in Missouri, said she feared potential side effects from the vaccine and got a shot only because her employer required it.

As the country’s vaccination campaign slows and doses go unused, it has...