As of Wednesday, 1,198 students and 12 staff members from the University of Colorado Boulder have tested positive for COVID-19. There are also 104 probable cases, according to the Colorado Department of Public Health and Environment (CDPHE).

This is the single largest outbreak in the state since the COVID-19 pandemic began, almost doubling positive count of the last biggest outbreak.

The previous largest outbreak was at Sterling Correctional Facility where 566 prisoners and 53 staff members tested positive for COVID-19. Three deaths were connected to the Sterling outbreak.

Wednesday was the first day of all-online classes at CU Boulder, a two-week plan announced Monday to address the rise in COVID-19 cases before the CDPHE data came out.

“I know this situation is extremely difficult, and I wish, as I know we all do, that our circumstances were very different,” said CU Chancellor Phil DiStefano in a letter. “The next two weeks are about more than our ability to see each other in person.”

“The risks to our broader community are too great, and COVID-19 spreads too easily, for any further noncompliance with public health measures to go without immediate consequences.”

CU students hosting or attending large gatherings will now result in an immediate 10-day suspension.

Over a dozen students received notices of this over the weekend, DiStefano said Monday.

Before switching to online learning, CU attempted to address increasing COVID-19 numbers by issuing a two week stay-at-home notice with Boulder County Public Health on Sept. 15. The notice recommended all students living in Boulder self-quarantine for 14 days, only leaving residences to attend class, work, eat or go to the gym.

There have been no deaths linked to the CU outbreak so far. One student was hospitalized as a result of COVID-19 but has been discharged, according to Boulder County health officials.

CDPHE reports smaller active COVID-19 outbreaks at Colorado College, Colorado State University, Metro State University, Regis University and the University of Denver.