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A booster dose of the Johnson & Johnson COVID-19 vaccine helped reduce hospitalizations and serious illness among South African medical workers as the Omicron variant swept the nation, a new study says
About 69,000 health care workers were given a booster dose of the J&J vaccine between Nov. 15 and Dec. 20, according to the study published in medRxiv.
The booster provided about 85% effectiveness against hospitalization because of COVID, the study says.
"Our data demonstrates that a homologous boost given to (health care workers) 6-9 months after the initial … vaccine is protective against hospital admissions," the study said.
Linda-Gail Bekker, the study's co-lead investigator, told Reuters that the study "reassures us that COVID-19 vaccines continue to be effective for the purpose they were designed, which is to protect people against severe disease and death."
The study is good news for Johnson & Johnson, which has come under criticism since the vaccine was rolled out.
Earlier this month, a panel of experts that advises the U.S. Centers for Disease Control and Prevention on vaccines said the Pfizer and Moderna vaccines are the preferred vaccine for adults because the J&J carries the risk of a rare but potentially fatal side effect that causes blood clots.
Johnson & Johnson welcomed the results of the new study.
"This adds to our growing body of evidence which shows that the effectiveness of the Johnson & Johnson COVID-19 vaccine remains strong and stable over time, including against circulating variants such as Omicron and Delta," Mathai Mammen, M.D., the global head of Janssen Research & Development, said in a statement.
Health authorities around the world hoped the J&J vaccine would help bring COVID under control in undeveloped nations. The initial J&J vaccination requires only one shot, compared to two shots of the mRNA-based Pfizer and Moderna vaccines, and doesn't need extreme refrigeration for transport and storage, unlike the Pfizer and Moderna vaccines.
medRxiv. "Vaccine effectiveness against hospital admission in South African health care workers who received a homologous booster of Ad26.COV2 during an Omicron COVID19 wave: Preliminary Results of the Sisonke 2 Study."
Reuters. "J&J booster slashes Omicron hospitalisations -S.African study"
Johnson & Johnson. "Johnson & Johnson COVID-19 Vaccine Demonstrates 85 Percent Effectiveness against Hospitalization in South Africa when Omicron was Dominant"
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Cite this: J&J Booster Reduced Hospitalizations in South Africa, Study Shows - Medscape - Dec 30, 2021.