As cases drop, health officials track new coronavirus variant

With nearly 64% of American adults now at least partially vaccinated for COVID-19, CDC Director Dr. Rochelle Walensky says new infections are down 94% from where they were in the January peak.

"It gives me so much how to report these declines in cases, hospitalizations and deaths," Dr. Walensky says.  "It is, in part, a result of our ongoing efforts to vaccinate so many Americans."

Still, Georgia and other southern states are lagging behind in the US, when it comes to vaccinating residents.

As of Tuesday, the CDC says 51% of Americans had received one dose of the vaccine and 42% were fully vaccinated.

In Georgia, 41% of residents have received one dose of the vaccine, and just over a third, or 34%, were fully vaccinated.

Dr. Anthony Fauci, Director of the National Institute of Allergy and Infectious Diseases, acknowledged the US could fall short of the Biden Administration's goal of getting 70% of American adults partially vaccinated by early next month.

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"We've always held that July Fourth is not the end of it," Dr. Fauci says. "We want to reach 70% of the adult population by the Fourth of July. I believe we can.  I hope we will.  And, if we don't, we're going to continue to keep pushing."

One concern with the lagging pace of vaccinations in some states, Dr. Fauci says, is a new, more contagious, and likely more severe variant of the virus, known as the delta variant, or the B.1.617 strain.

The variant, which triggered a deadly surge in infections in India, has now been detected in 60 countries, including the US, where, Dr. Fauci says, it now makes up more than 6% of all sequenced COVID-19 cases.

In the U.K., where the delta variant is now the dominant strain, Dr. Fauci says, transmission rates are highest in younger adults between the ages of 12 and 20.

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He is concerned the same scenario could play out in the US.

There are also signs, Dr. Fauci says, one dose of the coronavirus vaccine may not offer much protection against the delta variant.

He says the Pfizer-BioNTech and AstraZeneca vaccines were 88% effective in protecting fully vaccinated people from symptomatic disease caused by the delta variant.

But, three weeks after the first dose, the vaccine provided only 33% protection against the variant.

Studies show the mRNA vaccines offer about 80% protection two weeks after the first dose.

Fauci is concerned those who have not yet had their final dose of the vaccine could be vulnerable.

"Particularly if you've had your first dose, make sure you get that second dose," Dr. Fauci says.  "And, for those who have not been vaccinated yet, please, get vaccinated."

If you are vaccinated, he says, you are at risk.

"If you get vaccinated, you dramatically diminish the risk of getting infected and almost eliminate the risk of serious disease," Fauci says.

There are ongoing discussions about whether Americans need to get a COVID-19 booster shot in the fall or winter.

Dr. Fauci says a booster of the original vaccine, which targets the alpha, or "wild-type," strain of the virus will likely offer enough protection against new variants. 

"There is rather good protection that spills over against multiple variants," Fauci says. says.  "So, you can boost against the "wild-type" and still cover the variants, including the 617."

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