SOLANO COUNTY (CBS13) – Masks are mandatory in Yolo and Sacramento counties effective on Friday, but just down the highway, it’s a different story.

In West Sacramento, people flocked to and from businesses with their masks on once again. In Vacaville, people still have a choice if they want to mask up.

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Though, some businesses can make that decision – too. A Vacaville Walmart asks everyone to put on a face covering as they walk inside. It’s a comfortable feeling for Michael Diadeh, who doesn’t want to be the reason someone gets sick.

“Don’t be the one to help spread, right?” Diadeh said. “We’re all in this thing together, and if everyone does their part – there wouldn’t be a need for a mandate.”

He wishes others in his county thought like him, too. But not everyone does.

“If they can show me absolutely where it helps,” Scott Hansen, who lives in Solano County said. “Then maybe I would change my mind.”

But many health officials, including the U.S. Centers for Disease Control and Prevention, say masks do help stop the spread of the dangerous coronavirus Delta variant, even among the vaccinated. Experts have said they can also stop more mutations before they start.

Yolo County’s Dr. Aimee Sisson said mask recommendations aren’t enough, and requirements may be necessary.

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“We now know that they’re less protected from getting an infection. If our hope is to slow the spread in the community, particularly with the unvaccinated, it’s important we take extra precautions right now,” Dr. Sisson said. “I would be seriously considering it in any location that’s in that substantial or high range.”

Transmission is that high in most of California, including Solano County. But Dr. Bela Matyas won’t implement a mask mandate or all – because he’s not seeing transmission within businesses or between vaccinated people. Simply put, he said the Delta variant doesn’t pose any new concerns.

CBS13 asked Dr. Matyas about the recently leaked CDC data. It claims the Delta variant is as contagious as chickenpox and transmission is happening even in some people who are vaccinated.

He referenced the Provincetown, Mass. outbreak that led the CDC to recommend masks for everyone, once again. He said some of the CDC data has been oversimplified, and breakthrough infections should be expected.

“Provincetown events that caused this outbreak are like South Lake Tahoe in summer,” Dr. Matyas said. “When you have people on top of each other, you don’t need to come up with new fancy transmission mechanisms. It spreads so quickly in a grossly overcrowded environment.”

In regards to masking up to avoid further mutations, Dr. Matyas said, “The only way to stop mutations is to eradicate the disease. Eradicating COVID is just impossible – it’s a nonstarter.”

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Still, many support a mask mandate in hopes of curbing COVID’s spread, while others are happy they’re still free to make their own choices.