PHILADELPHIA (CBS) – Despite the higher vaccination rate, the CDC says there’s a “substantial” level of COVID-19 transmission in parts of our area. Officials say it’s mostly driven by the fierce Delta variant and is mainly impacting people who aren’t vaccinated.

There are breakthrough cases and that’s forcing governments and businesses to act.

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“I wasn’t shocked but I was worried,” University of Pennsylvania Dr. Fredric Bushman said. “The rest of the country like New York has seen Delta spreading aggressively a little ahead of us. Florida rates are soaring and now it’s here.”

The Delta variant is rearing its head in the Philadelphia region. The CDC now says the virus continues to spread at substantial rates throughout Pennsylvania, Delaware and New Jersey.

Despite breakthrough cases, Dr. Bushman, who runs the lab at the University of Pennsylvania, says the biggest line of defense is getting vaccinated.

“You’re still greatly helped by taking the vaccine, but still there’s the danger now that the virus may infect vaccinated people and spread from those people,” Dr. Bushman said.

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It prompted New Jersey Governor Phil Murphy to announce a mandate on Monday that all workers in high-risk congregate settings be fully vaccinated or undergo routine testing by Sept. 7. They include people who work in hospitals, nursing homes, and prisons. He also opened the door to the private sector to follow suit.

“While this policy specifically impacts the healthcare facilities and congregate living settings listed, there is nothing stopping any employer from implementing at least as rigorous a policy,” Murphy said.

That’s already happening in Philadelphia. As of Aug. 1, the owner of Martha, based in Kensington, is requiring all guests and employees to be vaccinated. The policy also applies to their restaurant in Rittenhouse Square named SALLY. Guests will have to show proof of vaccination to dine in the dining rooms.

“We’ve been on a roller coaster of emotions through this entire pandemic and it’s not over. We are really listening to our staff and we care about their health. We care about their safety,” Martha General Manager Olivia Caceres said.

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Officials in Philly and Camden are both holding news conferences on Tuesday. Philly’s begins at 11 a.m. and Camden’s is at 1 p.m. You can watch them both on CBSN Philly.