BOULDER, Colo. (KDVR) – A public health order issued Thursday by Boulder County Health bans people age 18 to 22 from gathering in groups in the city of Boulder and requires residents living at certain addresses to stay at home for 14 days.

Boulder County Health Department said it issued this order because COVID-19 cases have been on the rise in Boulder county for almost three straight weeks with the majority due to transmission among Boulder residents aged 18-22, particularly those attending the University of Colorado Boulder and living in the Hill neighborhood.

The health order bans people ages 18 to 22 from participating in any gatherings of any size, whether indoors, outdoors, on or off campus, or with individuals of any age in the city of Boulder.

The order also identifies 36 residences in the Hill neighborhood that the health department said continue to violate public health orders. The new health places residents at those 36 residences under a “Stay-At-Home” order, requiring them to isolate at home for 14 days.

The order goes into effect at 4 p.m. on Thursday and lasts for 14 days.

Any people caught violating the public health order face up to 90 days in jail and a $1000 fine. Those who violate the public health order and attend CU face discipline through the university, including possible explusion.

“Governor Polis knows that the better students do avoiding gatherings, the sooner they can get back to in person learning and the sooner they can resume their regular activities. We know this isn’t the school year that any of us imagined, but urgent action is needed to prevent further spread in the community,” a statement from the governor’s office said.