Pfizer, Moderna vaccines 90% effective after 2 doses, CDC real-world study finds

ATLANTA — New data about COVID-19 vaccines in real world scenarios is part of a growing body of evidence about how effective they are.

The Atlanta-based Centers for Disease Control and Prevention released findings of a real-world study Monday that show the Moderna and Pfizer vaccines are 90% effective at preventing all infections.

“It’s really good news, again, for vaccines,” said Dr. Colleen Kelley with Emory University.

[SPECIAL SECTION: COVID-19 Vaccine in Georgia]

Kelley told Channel 2′s Matt Johnson that vaccine effectiveness usually changes when it is out of a clinical setting, but the COVID-19 vaccines are exceeding expectations.

“With a new vaccine or a new product, once it gets out into the real world, you see a little bit less effectiveness. But that’s not the case with these Pfizer and Moderna vaccines,” she said.

The CDC studied nearly 4,000 vaccinated people over 13 weeks who were mostly front line health care workers. Those who received one dose were 80% less likely to get infected after two weeks. Those who received two doses were 90% less likely.

“This study, along with a few others, are really giving us the great news that vaccination also cuts down on asymptomatic disease as well, which is wonderful,” Kelley said.

Nearly a quarter of Georgia’s population has received at least one dose of a COVID-19 vaccine. More data on the vaccine could inspire more to get vaccinated.

“We got people who want to volunteer,” Ashley Chen said.


Ashley and Alicia Chen run the Georgia Vaccines Hunters Facebook group with more than 10,000 members. They help crowdsource information about vaccine availability across the state.

With the supply catching up to demand, the Chens want to use the group to help convince skeptics to get vaccinated.

“We’ve probably scheduled hundreds of appointments through just our volunteer group,” Alicia Chen said. “We want to encourage people to get out to protect themselves and protect their communities.”

Courtney Sheeley is with the South Health District in Valdosta. She said now that everyone 16 and over can get a vaccine, there are more people in rural parts of the state who are interested.

“Some of our health departments that have had openings, you can almost get a same day appointment. Now, they’re booked up into April,” Sheeley said.

There is a lot of data out there on vaccines, but there are still some burning questions left. How long does the vaccine protect you? How well do they stop transmission?

Researchers said they are optimistic the vaccines will continue to outperform expectations, but understand more research is needed in those areas.

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