By City News Service

San Diego County health officials reported 302 new COVID-19 infections Monday, raising the cumulative total to 11,096 cases, while the death toll remained unchanged at 338.

The 302 new cases represent the second-largest increase since the pandemic began and 5% of the 5,831 tests reported Monday. The largest increase in cases yet came on Sunday, when 310 tests, or 7% of that day’s tests, were reported as positive.

The numbers are concerning to public health officials, who had praised San Diego County for avoiding the brunt of the pandemic’s ill effects so far.

“The message here is very clear,” said county Supervisor Nathan Fletcher. “The dangers from coronavirus are real.”

Dr. Christian Ramers, an Infectious Disease Specialist and Chief of Population Health Centers of San Diego, said the surge isn’t much of a shock.

“I think this was actually expected as we opened up the economy and opened up businesses, and allowed people to come into restaurants,” Dr. Ramers said. “This was expected.”

Another three community outbreaks were reported Monday, raising the number reported in the last week to 10 — the most in any week’s span since the pandemic began in early March.

Community-transmitted COVID-19 outbreaks activated one of the county’s public health triggers last week, placing a pause on any additional openings allowed by the state.

“We continue to implore the public to wear facial coverings and avoid having gatherings at your home,” Fletcher said.

After public health officials Thursday reported eight community-transmitted outbreaks in San Diego County within a week, Fletcher said any further openings allowed by Gov. Gavin Newsom wouldn’t be implemented until numbers go down.

Dr. Ramers said sticking to what health experts have been preaching is key.

“The things that work are keeping your distance from each other, washing your hands, covering your face,” he said.

You really have to be perfect. It doesn’t do any good to wear a mask 90 percent of the time if you just rip it right off and expose yourself. It only takes that one exposure.

– Dr. Christian Ramers, an Infectious Disease Specialist and Chief of Population Health at Family Health Centers of San Diego

Young people managed to stay away from infections early on in the pandemic, but that trend has changed since parts of the economy have reopened. And while younger people were at first thought to be less at risk from the side effects of COVID-19, Dr. Ramers said there is still a lot left to learn.

“I’ve seen people from their 20s die from this disease and I’ve seen people in their 20s or 30s that recover fine and then have four to six to eight weeks of a terrible recovery that we don’t really fully understand yet,” he said.

As part of the 13 public health triggers announced earlier this month, the county could take industry-specific actions, pause all reopening efforts or even dial back reopenings if enough of the metrics rise above a certain threshold. The threshold for community outbreaks — defined as three or more lab-confirmed cases from different households — was fewer than seven in a week’s span.

Two new community outbreaks were reported Friday, offsetting three outbreaks which “fell off” the county’s one-week rolling monitoring period.

The total number of outbreaks in a community setting is now at seven, which keeps the metric at a caution level.

Keep reading on NBC San Diego…