On the checklist of things to do before arriving on campus this fall, college students now have another requirement: They must get vaccinated against the coronavirus.

Dozens of universities have announced that COVID-19 vaccines will be mandatory for all students hoping to return to in-person learning this September. Yale University was one of the first schools to introduce this requirement, with President Peter Salovey informing the campus that the vaccine mandate would apply to all undergraduate, graduate, and professional school students before the federal government had even approved vaccine use for students younger than 18 years old. The mandate is necessary, Salovey said, because vaccination is the only way the school can guarantee a minimal transmission of the virus.