OAKLAND (KPIX/AP) — The U.S. is getting a third vaccine to prevent COVID-19, as the Food and Drug Administration on Saturday cleared a Johnson & Johnson shot that works with just one dose instead of two.

Health experts are anxiously awaiting a one-and-done option to help speed vaccinations, as they race against a virus that already has killed more than 510,000 people in the U.S. and is mutating in increasingly worrisome ways.

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The FDA said J&J’s vaccine offers strong protection against what matters most: serious illness, hospitalizations and death. One dose was 85 percent protective against the most severe COVID-19 illness in a massive study that spanned three continents — protection that remained strong even in countries such as South Africa, where the variants of most concern are spreading.

Shipments of a few million doses to be divided among states could begin as early as Monday. By the end of March, J&J has said it expects to deliver 20 million doses to the U.S., and 100 million by summer.

It appears America’s vaccination effort is about to get a big bump-up in speed.

“Remember when Biden said they were going to be 100 million doses given a hundred days?” said UCSF epidemiologist George Rutherford. “Now (we’ve seen) 57 million given and 36 days or something. Pretty good!”

The arrival of a third vaccine adds to some other good news on that front. Pfizer and Moderna expect their shipments to double or possibly triple in the coming weeks. The bad news is that the nationwide decline in coronavirus cases appears to be slowing and several virus variants are spreading.

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“I think if there’s going to be a problem with the variants, it’s going to be that we’re going to see a little burst of transmission and outbreaks here and there,” Rutherford told KPIX. “And that’s when the Johnson & Johnson vaccine becomes really helpful because you can go and vaccinate around those — try to limit the spread — not only through contact-tracing and isolation but by going out to the next layer around and vaccinating around them.”

Having a new vaccine provides more supply with increased options and greater ease of deployment, something that will mean half the legwork in areas where delivering the vaccine can be toughest.

“Even though it’s nice to have the (Oakland) Coliseum (vaccination site) … urban populations, people of color, need other avenues to be able to get vaccinated coming to them and bringing the vaccinations to them,” said Dr. Gerard Jenkins, chief medical officer at Oakland’s Native American Health Center. When FEMA offered to bring its mobile vaccination site to his parking lot, he skipped the internet and started making flyers.

“We went up and down international Boulevard,” he said. “Handing them out to people in the community, saying ‘here, are you a health care worker? Are you in food or agriculture?'”

With the arrival of the Johnson & Johnson vaccine, Dr. Jenkins’ job should get much easier soon.

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