By Stephanie Stahl

PHILADELPHIA (CBS) — The COVID-19 Delta variant is now more dangerous than previously revealed, according to concerning new documents from the U.S. Centers for Disease Control and Prevention. This comes as COVID cases continue to spread in the Philadelphia region, with several additional local counties now having substantial rates of transmission.

The increasing cases are mainly among people who are not vaccinated, but we now know that even people who are vaccinated can still spread this virus.

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Acknowledge “the war has changed” is among the startling revelations from internal CDC documents outlining dangers of the Delta variant that’s spreading like wildfire, even to and from people who are vaccinated.

“I am concerned about that,” Dr. P.J. Brennan with Penn Medicine said. “It does seem capable of infecting vaccinated people and vaccinated people do shed the virus.”

New data from the CDC shows the Delta variant causes more serious illness and is much more contagious than previously thought, with each infected person passing the virus to eight others.

“Tt’s much more contagious than the common cold,” Dr. Jonathan Reiner, an infectious disease expert, said. “It’s about as contagious as chickenpox, which is a very contagious virus.”

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The updated CDC map shows much of Central and South Jersey is now orange, meaning there’s a substantial transmission of the virus. The CDC says people in these areas should wear masks inside and it’s also currently a recommendation from the state.

“We were the first state in the country to mandate indoor masks and we were the last state to have that mandate in place so we’ve done it before and if we need to, we’ll do it again,” Gov. Phil Murphy said. “so we’ll continue to watch this like a hawk.”

The updated map now includes New Castle County in Delaware with a substantial number of covid cases, and Philadelphia is also orange for the first time in months.

“A lot of people who are eligible and not vaccinated yet,” Brennan said. “I’m worried as we approach the fall, we’re going to have another surge, even in this region.”

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This region has been in relatively good shape compared to other hot spots, but that could change. That’s why it’s so important for people to wear masks inside public places, even people who are vaccinated.

Stephanie Stahl