Preliminary results from the Sisonke study, which have not been peer-reviewed, found that for people who had received one vaccine dose, the booster improved protection against hospitalization to 85 percent from 63 percent.
The study, carried out by the South African Medical Research Council compared 69,000 healthcare workers in South Africa to a group of unvaccinated South Africans.
The trial took place in November and December but participants were enrolled before the current wave now sweeping across the country, allowing researchers to "evaluate the effectiveness of the Company’s Covid-19 vaccine specifically as omicron became the dominant variant in the country," Johnson & Johnson said in a statement.
U.S. & World
The Food and Drug Administration approved the Johnson & Johnson booster in October, but earlier this month the Centers for Disease Control and Prevention said people should get the Pfizer-BioNTech and Moderna boosters instead where possible, citing concerns over extremely rare blood clots.
Read the full story here at NBCNews.com