PITTSBURGH (KDKA) – Some school districts in our area have barely started in-person instruction and already have had to close because of positive COVID cases.

Just this week, the state announced mandated mask-wearing in schools starting September 7th.

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KDKA spoke with Infectious Disease Specialist, Dr. Matthew Moffa, who says the Delta variant was a game-changer, and one reason why we’re seeing cases go up in children. He also said that the mask mandate is huge because kids don’t have any other way to protect themselves.

Wearing a mask does not provide 100% protection, but doctors say they help immensely and the argument that wearing one harms students’ mental health is not a strong one, according to Dr. Moffa with Allegheny Health Network.

That’s because the alternative, not wearing a mask, he says is more dangerous for kids.

What’s alarming for parents, it’s possible their kids could be carrying the virus and not even know it. Some children show no symptoms and it’s possible they’re spreading it to others.

That’s just one reason why, doctors say, we’re seeing the high spread in kids.

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However, it’s also because those 12 and under can’t get vaccinated.

“Kids are not immune to this,” he said. “We’re seeing the highest rate of hospitalizations in the pediatric population in the entire country right now. So if we don’t take protective measures in schools, then you’re going to see tons of transmissions, that’s why wearing masks are so important.”

As for a vaccine for those younger than 12, health experts say it’s possible we could see that at the end of the year.

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Now, besides the Delta variant, there’s a new one the medical community is talking about. It’s called the “Mu” variant.

Dr. Moffa says there are reports it is more contagious, but there’s no strong evidence at this time to support that.

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“Even in the United States, when we track all of the variants here, over 99% of them are Delta,” he explained. “So it’s too early to say there’s a new variant or a new problem variant that has arisen. We’re still dealing with Delta, which is the main player here.”