COVID vaccine booster shots were rolled out, and about 40 percent of US adults said they did not plan on getting a booster.
COVID-19 vaccines used in Brazil are from three ... the technology used in the Moderna and Pfizer shots, the researchers said. In clinical trials, J&J's vaccine had shown an 85% efficacy.
Data from a late-stage study shows that Moderna's (MRNA) next-generation COVID vaccine induces a more robust immune response compared with its previously approved bivalent COVID vaccine.