The growing number of COVID cases in the U.S. indicates a major divide between the vaccinated population and those who choose to remain unvaccinated.

The 7-day moving average of new cases increased by 16% last week, according to CDC data, and roughly 93% of those cases were among counties with low vaccination rates.

“The problem is we have a tale of two pandemics,” Dr. Andre Campbell, a California-based ICU physician and trauma surgeon, said on Yahoo Finance Live recently (video above). “Where I live in San Francisco… We have 70-80% of people vaccinated. But if you go to other places in the South, the vaccination rate is 30 to 40%.”

Much of this stems from political polarization: Republican-dominated areas, some led by politicians who have added vaccine skepticism to their messaging, generally have lower vaccinated rates.

“What I’m fearing is this: These pockets where people are not vaccinated in the South, what happens in the fall when it comes back again — which it will — there are going to be outbreaks,” Campbell said. “And things like what’s going on in Missouri right now: In Missouri, there’s a horrible outbreak among unvaccinated people and they’re calling for help.”

In Missouri, which is seeing a 7-day moving average of 1,597 new cases, 73% of the cases have been linked to the Delta variant, according to the CDC. Only 39.8% of the population in the state is fully vaccinated.

“It’s almost like New York again, where they’re placing calls for doctors, respiratory therapists... so what we’re trying to do is get to the point where we could get more people vaccines because that’s the thing that will get us out of this,” Campbell said.

'If you are vaccinated, you are very protected'

There are currently three vaccines available in the U.S.: Pfizer (PFE)’s, Moderna (MRNA)’s, and Johnson & Johnson (JNJ)’s.

All three are said to be at least somewhat effective against the strains of the virus, including the newer Delta and Lambda variants.

“In Maryland, they just reported that 99% of people who got COVID were not vaccinated,” Campbell said. “The reality is the vaccines protect you now, even against the Delta variant. There’s a Lambda variant today. They just came out with another double variant and you have to remember, these viruses are built to mutate. So the more they’re out in the general population of unvaccinated people, the more it puts people at risk.”

The percentage of those vaccinated with at least one dose in Mississippi is just 37%, with Louisiana not far behind at 39%. Other states lagging include Tennessee, Alabama, Wyoming, and Idaho. Concurrently, most of those states are seeing a significant uptick in cases over the last 14 days.

“The thing we’re worried about is that in the last week or so, the rate of infections [nationally] has gone up about 50%,” Campbell said. “That may be tied to the reopening and people not masking because the masking mandates are starting to go away. These are mainly in people who are not vaccinated. If you are vaccinated, you are very protected against all the variants we have right now.”

Consequently, Campbell stressed the importance of trying to convince unvaccinated individuals to reconsider their discussion.

“What we have to do is we’re going to have to strike up a very subtle discussion to make sure people understand that we want to make sure they’re protected,” Campbell said. “There will be some masking mandates, because this thing is not going to go away like we hope it will unless we go on an international campaign to eradicate this thing, much like what happened with smallpox and other things like that, because we’re not there yet right now.”

Out of more than 157 million people vaccinated in the U.S., there have been under 5,200 breakthrough cases that led to hospitalization or death as of July 6. That’s a paltry 0.003% rate.

"You’re not a guinea pig," Campbell said, referring to the safety of the vaccine. "310 million people have gotten this thing and they’ve been saved. I think the message is: 'It’s safe. It’ll protect you and you’re not going to die, or you’re not going to get really sick.'”

Furthermore, as various version of the virus continue to circulate, unvaccinated people are at risk.

“If you’re unvaccinated, you’re in trouble," Campbell said. "If you’re vaccinated, you’re going to be safe.”

Adriana Belmonte is a reporter and editor covering politics and health care policy for Yahoo Finance. You can follow her on Twitter @adrianambells and reach her at [email protected].

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