Coronavirus case numbers at the University of Idaho doubled again last week, with the outbreaks tied to the fraternity and sorority community.

The U of I reported 67 new cases through Friday, up from 25 cases the preceding week.

University and public health officials do not believe the virus is spreading through classroom contact. However, the university is allowing faculty to shift face-to-face classes to online instruction this week.

“The outbreak seems isolated to fraternities and sororities, but we will increase our general surveillance testing outside the Greek system this week to verify,” President C. Scott Green and interim Provost and Executive Vice President Torrey Lawrence said in a memo to the campus community Monday.

Eight Greek houses were placed in quarantine last week, the U of I Argonaut reported.

The spike in cases also corresponded with a sharp uptick in positive test results. In all, nearly 12 percent of tests came back positive last week. Many health experts want to see a community’s positivity rate at 5 percent or lower.

However, Green and Lawrence attribute last week’s high positivity rate to testing focused on fraternities and sororities.

Click here for a look at coronavirus numbers across the state’s colleges and universities.