(Bloomberg) -- U.S. Supreme Court Justice Amy Coney Barrett refused to block Indiana University’s requirement that all students be vaccinated against Covid-19 for the fall semester unless they have a religious or medical exemption.

Barrett gave no explanation as she turned away an emergency request from eight students who said the vaccine mandate violated their constitutional rights.

The case marked the first time the nation’s highest court has acted on a vaccine mandate. It comes as universities and employers across the country are moving to require Covid vaccinations in an effort to stem the rapid spread of the Delta variant.

The Indiana University policy applies to faculty and staff as well as students. Those who receive a religious or medical exemption must wear masks in public spaces and be tested twice a week.

In backing the university, a federal appeals court cited a 1905 Supreme Court ruling that said states may require people to get vaccinated against smallpox. Writing for the three-judge panel, Judge Frank Easterbrook said the Covid case is “even easier” than the smallpox dispute because Indiana allows religious and medical exemptions.

Easterbrook said people who don’t want to be vaccinated “may go elsewhere.” The suing students “have ample educational opportunities,” he wrote.

Six of the eight suing students have claimed a religious exemption but say they object to having to wear masks and be tested. In court papers, the group said the university “is treating its students as children who cannot be trusted to make mature decisions” and has substituted itself for students and their physicians.

The case is Klaassen v. Trustees of Indiana University, 21A15.

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