Frat parties at UC Berkeley have been linked to a spike in coronavirus cases and its reopening is now in jeopardy

• The University of California, Berkeley, blamed a surge in coronavirus cases on frat parties.
• Increased cases could change its plans to reopen, warning "it's becoming harder to imagine bringing our campus community back in the way we are envisioning."
• There were just 23 coronavirus cases since the beginning of the outbreak — and then 47 new cases were found in only one week.
• "The majority of these new cases stem from a series of recent parties connected to the CalGreek system," said the university.

The University of California, Berkeley, is rethinking its plans to reopen after it linked a surge in its coronavirus cases to frat parties.

In a statement on Wednesday, college officials said that its health service had found just 23 coronavirus cases since the beginning of the outbreak — and then 47 new cases were found in a week.

"Over the last week or so we have seen a notable increase in UC Berkeley students testing positive for COVID-19. It is concerning," the statement read, warning that the cases could alter its reopening plans.

Most of the cases were traced to parties held within its Greek system of sororities and fraternities, and then spread to households and other gatherings.

"Generally, these infections are directly related to social events where students have not followed basic safety measures such as physical distancing, wearing face coverings, limiting event size, and gathering outside," it said.

It said the college health services have been tracing the people who have been in contact with those who tested positive about quarantining and testing.

But it warned that the new cases might upend the plans underway to get more students and staff back.

"However, at the rate we are seeing increases in cases, it's becoming harder to imagine bringing our campus community back in the way we are envisioning," said the statement.

But it added that "If we can keep our COVID-19 case numbers low, we can continue to move forward with our fall semester plans."

It said that "The fall semester will look and be very different," with all students and staff required to wear a mask "unless they are completely alone in their room or office."

"There will be distancing measures in every conceivable area across campus."

UC Berkeley also said it is trying to figure out how it can create "small 'bubbles' of 10-12 students living on campus."

It urged students not to attend gatherings and parties or go into crowds or socialize indoors with people they're not living with.

It has started opening some research buildings across the campus, and said it would judge the opening of future ones "depending on the rate at which the coronavirus spreads."

California's infection rate has recently surged, and Gov. Gavin Newsom warned that COVID-19 cases were also increasing among young people in late June.

"There is a sense that a lot of young people are, well, you're young, and so you feel a little bit more invincible," he said. "But respectfully, often, that can be a selfish mindset.'