HARRISBURG, Pa. (WHTM) — The Delta COVID variant has health leaders concerned, which is intensifying a push to get more people vaccinated.

The CDC says the Delta variant makes up around 10% of new cases in the U.S. That may not seem like a lot, but it’s spreading quickly and seems like it could be deadlier than the original COVID strain.

In a press conference on Friday President Biden pleaded with the public to get vaccinated.

“Get vaccinated. Now. Now. Don’t put it off,” Biden said.

This comes as worry increases around the Delta variant. Dr. Mohammad Ali of Penn State Health explained part of that is because health officials think it could soon become the leading COVID strain in the U.S.

“This variant is more transmissible, which means it’s going to spread really fast,” Ali said. “We would probably in the next few weeks see that this variant would become dominant and the reason for that is because our behavior is changing. Secondly, it is more transmissible,” Ali said.

Not only is it spreading fast, but the Delta variant is also considered more dangerous. It’s causing more severe sickness and hitting younger people particularly hard.

But CDC Director Dr. Rochelle Walensky says there is some good news.

“As worrisome as this Delta strain is with regard to its hyper transmissibility, our vaccines work. Right now they are working,” Walensky said.

Not everyone has that vaccine protection though.

“If I’m fully vaccinated I’m very confident about at least my health. But what I’m concerned about is there are lots of unvaccinated or partially vaccinated people in the community still,” Ali said.

There is some reason for everyone to worry.

“As viruses mutate they do so with some advantage to the virus. One of those advantages could be that it evades our vaccines and that’s really what we’re trying to prevent,” Walensky said.

That’s why they believe it’s important now to get out as many shots as possible.

“The push should be to vaccinate, fully vaccinate, as many people as we can in the shortest possible time,” Ali said.

Dr. Ali says right now he doesn’t believe there’s a booster being developed specifically for this variant, because it seems like the current vaccines are effective against it. He noted that could change as the virus mutates or if a lot of already vaccinated people seem to get it.