INDIANAPOLIS (AP) — Indiana University can require its roughly 90,000 students and 40,000 employees to get vaccinated for COVID-19 under a federal judge’s ruling that might be the first of its kind regarding college immunization mandates.

In a ruling dated Sunday, U.S. District Judge Damon Leichty in South Bend rejected a request from eight IU students who sought to block the requirement while they pursue a lawsuit claiming that the university’s policy violated their constitutional rights by forcing them to receive unwanted medical treatment.

James Bopp, a conservative lawyer representing the students, said Monday that he plans to appeal the ruling, which he believes is the first by a federal judge in challenges to such mandates, which have been imposed by hundreds of U.S. public and private colleges.

Leichty wrote that the students haven’t presented evidence showing they could prevail in the case, and that the Constitution “permits Indiana University to pursue a reasonable and due process of vaccination in the legitimate interest of public health for its students, faculty and staff.”

Leichty, who held a hearing on the case last week, said the plaintiffs could seek medical or religious exemptions offered by the university, or they could take the fall semester off or attend another school.

University officials defended the vaccination policy as one “designed for the health and well-being of our students, faculty and staff.”

“We appreciate the quick and thorough ruling which allows us to focus on a full and safe return,” the university said in a statement. “We look forward to welcoming everyone to our campuses for the fall semester.”

Bopp said he would ask an appeals court to block the university’s policy from taking effect.

“An admitted IU student’s right to attend IU cannot be conditioned on the student waiving their rights to bodily integrity, bodily autonomy, and consent to medical treatment like IU has done here,” he said.

Similar lawsuits have been filed in federal courts in Connecticut and California, Bopp said. College officials across the country have struggled with whether they have the authority to require student vaccinations, which some see as key to returning campus to in-person classes and other normal activities.

Indiana law currently requires students at state residential colleges and universities to get immunized for six diseases — diphtheria, tetanus, measles, mumps, rubella and meningitis. Students in public K-12 schools are required to get vaccinated for an additional five diseases.

The plaintiffs in the lawsuit, who range in age from 18 to 39, maintain that their age group is at low risk of severe cases of COVID-19 and that they face possible dangers from the vaccine that is being administered under federal emergency use authorization.

Leichty, who became a federal judge in 2019 after his nomination by then-President Donald Trump, faulted a doctor who testified against IU’s policy for using “soft and inconsequential language” and cited the extensive review by federal health agencies to confirm the safety of the three available COVID-19 vaccines.

“Progress has been made because of the vaccine, not despite it,” Leichty wrote. “To the extent that lingering medical and scientific debate remain … the court remains resolved that Indiana University has acted reasonably here in pursuing public health and safety for its campus communities.”

The lawsuit was filed after IU officials announced in May that the school would require all students and employees to receive COVID-19 vaccinations for the fall semester. Students who don’t comply will have their registration canceled and workers who don’t will lose their jobs.

IU initially was going to require students and employees to provide immunization documentation. That sparked a conservative backlash, with nearly all Republican members of the Indiana Senate signing a letter calling the policy a “heavy-handed mandate goes against many of the liberties on which our founders built our democratic republic.”

A non-binding opinion from Republican state Attorney General Todd Rokita’s office called the policy illegal under a new state law banning the state or local governments from requiring vaccine passports.

In response, IU made providing proof of vaccination optional and is allowing students and employees at its seven campuses to attest to their vaccination in an online form.