SAN FRANCISCO (CBS SF) — As omicron cases have soared in San Francisco so have calls to 911, straining the system and eliciting a plea from officials Saturday for local residents to limit calls to severe medical emergencies.

San Francisco Fire Chief Jeanine Nickolson said calls to 911 for medical assistance have jumped from 300-330 a day to more than 400 over the last week.

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“We are seeing a surge in 911 calls which is putting a strain on the system and what we are also seeing is many of our members off with COVID,” she said during a Saturday news briefing. “So there is a supply and a demand issue.”

“We are really urging people to only call 911 for life-threatening emergencies,” she continued. “Please don’t call 911 to ask for a COVID test or because you have a cold or minor flu symptoms. We really want to keep our ambulances available to people having a heart attack or strokes…It is the transport side of things that is really challenging for us right now.”

Nickolson told reporters just like the local community, her department has been hit hard by the omicron outbreak.

“We have about 140 people off that are COVID positive right now,” the chief said.

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Dr. Susan Ehrlich, chief executive officer Zuckerberg San Francisco General, also took part in the briefing. She said just like the 911 dispatch center, her emergency department was also being overwhelmed.

“We’ve never seen anything quite like this during the surges we’ve had so far,” she said. “So please don’t call 911, don’t walk into an emergency department either because you want a COVID test or because you are having mild symptoms of COVID.”

“Most cases of COVID are mild and you can stay home,” Ehrlich added. “If you have symptoms if you’re feeling sick, you should stay home, take care of yourself and try to stay away from other people as much as possible.”

Earlier in the week, Contra Costa County officials made a similar plea. The surge of cases in the county has led to about 100 more calls per day than 911 normally receives.

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“I think it is fair to say that there’s a bit of a perfect storm brewing here in terms of impacts on our health care system in general,” said Steve Hill with Contra Costa County Fire.