By Stephanie Stahl

PHILADELPHIA (CBS) — There are concerns sporting events could become super-spreaders for COVID-19 as Philadelphia’s coronavirus cases reach the highest they’ve been since mid-May.

Being vaccinated and outside is generally safe, but doctors say the Delta variant is a bit of a curveball. That’s because the Delta variant is so contagious and there’s the added problem of surging cases among people who aren’t vaccinated.

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Philadelphia has become red on the CDC’s COVID-19 transmission map, which means it’s at the highest level of community spread. There are also hot spots in all of South Jersey and Delaware.

“I think we’re at a dangerous time,” Dr. Tony Reed, with Temple Health, said.

Reed is the chief medical officer at Temple Health. He says the summer surge is driven by people who aren’t vaccinated. The hospital is bracing for another onslaught of COVID-19 patients.

“There is a lot of frustration, consternation and a lot of, ‘Oh geez, are we ready for this again?'” Reed said.

Temple has had the highest number of COVID-19 patients in the city.

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“There’s not a person inside the building who isn’t saying ‘Why won’t people get vaccinated, what’s wrong, why are they not seeing, not hearing, why are they not helping themselves,’ as we hold the hands of dying patients that’s what’s going through our minds,” Reed said.

He says the cities new inside masking mandate should help curb the surge.

“This is not the summer any of us imagined,” Acting Philadelphia Health Commissioner Dr. Cheryl Bettigole said. “We will be watching numbers closely, we may need to adjust safety measures if they continue to rise.”

Because the Delta variant is so contagious, there are concerns sporting events that attract thousands of fans could become super spreaders, even though being outside is safer masking isn’t required.

“It’s still in the air, it’s still out there, this is where social distancing still plays a factor,” Reed said.

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The CDC says people should wear masks at crowded public events and the best protection is to be fully vaccinated.

Stephanie Stahl