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The new data shows that the single-dose vaccine — one of three options available in the United States, alongside offerings from Pfizer/BioNTech and Moderna — is still "strong and long-lasting protection," Johnson & Johnson said. That protection "increases when a booster shot of the Johnson & Johnson vaccine is administered," and the booster shot was "generally well-tolerated when administered."
"It is critical to prioritize protecting as many people as possible against hospitalization and death given the continued spread of COVID-19. A single-shot COVID-19 vaccine that is easy to use, distribute and administer, and that provides strong and long-lasting protection is crucial to vaccinating the global population," Paul Stoffels, vice chairman of the executive committee and chief scientific officer at Johnson & Johnson, said in a statement.
"At the same time, we now have generated evidence that a booster shot further increases protection against COVID-19 and is expected to extend the duration of protection significantly," Stoffels added.
New data confirm protection of our single-shot #COVID19 vaccine in the U.S. https://t.co/jbZqo5xySN
The Janssen COVID-19 Vaccine has not been approved/licensed by FDA. https://t.co/Xnh5QY9N5o pic.twitter.com/JYHTAJW5bL
— Johnson & Johnson (@JNJNews) September 21, 2021
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According to a press release, a booster shot given at two months provided 94 percent protection against COVID-19, and a booster at six months after the initial dose offered a "12-fold increase in antibodies."
The U.S. Food and Drug Administration issued an emergency use authorization for the Johnson & Johnson vaccine on Feb. 27, and it is available in the U.S. for adults 18 and over. According to the FDA, "the most commonly reported side effects were pain at the injection site, headache, fatigue, muscle aches and nausea. Most of these side effects occurred within 1-2 days following vaccination and were mild to moderate in severity and lasted 1-2 days."
Pfizer earned FDA approval for its vaccine among people ages 16 and up last month. The vaccine is still under emergency use approval for kids aged 12 to 15 as the FDA continues to fully vet the shot.
Moderna, another two-dose option, was given emergency authorization for adults in December.
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