"You hope for a back-to-back home run," said UCSF epidemiologist, Dr. George Rutherford, who is optimistic about Moderna's pending Phase 3 trial results, because both the Pfizer and Moderna vaccines use messenger RNA and Pfizer's initial results indicate 90% efficacy.
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"They use essentially the exact same technology and I would assume that they're going to be very close in efficacy," said Rutherford. "You hope that it's equally effective because it doubles the number of doses available so we can immunize twice the number of people."
Rutherford said this about both the Pfizer and Moderna vaccines. "If you have a chance to get it, get it."
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Seattle-area resident, Neal Browning, did get it. He was the second person to receive Moderna's COVID vaccine during the phase one trial earlier this year. ABC7 news reporter, Kate Larsen, has been following him ever since.
He said Tuesday that he and his family remain healthy and COVID-free. "We've had no issues at all so far," he said.
"The more vaccines we get out there, the better, because it's going to be a limited run in how fast they can manufacture this and one company can't do it alone," said Browning.
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With Pfizer and Moderna reporting results within a similar timeline, it's possible both could get emergency use authorization from the FDA around the same time.
ABC 7 News reporter, Kate Larsen asked Dr. Rutherford, if multiple vaccines are available at the same time, will people get a choice?
"I think it's unlikely," he said. "I think they'll be allocated regionally, and so in California, we'll have one vaccine, or in Northern California we'll have one vaccine available. Maybe in the future, we'll have a situation in which multiple types of vaccines will be available, but I certainly don't anticipate it in the short run."
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The Pfizer, Moderna, and AstraZeneca vaccines all require two doses. Dr. Rutherford says it's possible people could get one product for their first shot and another for their second, especially if they use the same MRNA platform.
"You could imagine some stocking problems or they're running out of one and they might have to bridge with some scheme like that. But that's not an ideal solution, you start with one and finish with it."
According to Dr. Rutherford and Dr. Susan Buchbinder with San Francisco's Department of Public Health, the federal government will buy the vaccines and then distribute them at a state level.
A California task force will then distribute the vaccines to different counties and cities. The first groups prioritized for vaccination will be health care workers, people with co-morbidities at risk of severe COVID disease, and the elderly living in congregate settings.