On Dec. 30, Colorado State University implemented a COVID-19 booster requirement for on-campus students and staff. Now, the University of Colorado Boulder is following suit.

RELATED: CSU Students Need COVID-19 Boosters to Be on Campus

In a Monday (Jan. 11) letter, CU's Chief Operating Officer Patrick O'Rourke and Executive Vice Provost Ann Schmiesing announced that the university is instating "a new COVID-19 vaccine booster requirement" for the campus community.

Due to the Marshall Fire, students and staff will return to campus on Jan. 24, two weeks later than planned. Those on campus must receive their booster by Feb. 24 or five months after their second COVID-19 dose.

READ: Some Marshall Fire Victims Did Not Receive Emergency Alerts

"Vaccinations continue to provide the best defense against serious illness and hospitalization — and boosters provide significant additional protection for all of us, according to our own researchers and scientists and other health experts," read the letter. "The added protection of boosters will help ensure we are able to conduct the rest of the spring term as planned and will help protect those in the surrounding community who are most vulnerable to COVID-19."

Like CSU, CU Boulder will continue to honor vaccine exemptions. Students and staff who are not exempt can provide proof of their COVID-19 boosters to the MyCUHealth Portal.

The university's decision comes as cases of the omicron variant continue to rise in Boulder.

According to the letter, the "number of new cases per 100,000 residents in Boulder County skyrocketed from fewer than 200 to more than 900 during the past two weeks, and positivity rates during the period rose from less than 5% to more than 20%."

Answers to 25 common COVID-19 vaccine questions

Vaccinations for COVID-19 began being administered in the U.S. on Dec. 14, 2020. The quick rollout came a little more than a year after the virus was first identified in November 2019. The impressive speed with which vaccines were developed has also left a lot of people with a lot of questions. The questions range from the practical—how will I get vaccinated?—to the scientific—how do these vaccines even work?

Keep reading to discover answers to 25 common COVID-19 vaccine questions.

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