Johnson & Johnson’s COVID-19 booster shot showed up to 85% effectiveness in preventing hospitalization from the latest COVID-19 variant in a new study of South African health care workers.
The study has not been peer-reviewed, but results from the real-world analysis beginning in November showed effectiveness against COVID hospitalization rose from 63% to 84% in the first two weeks after a booster shot and increased to 85% in the next one to two months. At the time of the study, omicron was the dominant variant of COVID in South Africa.
A separate study, according to NPR, discovered a strong immune response specifically to the omicron variant in the blood of people who received the Johnson & Johnson booster. This result suggests more protection against severe illness. Like the South African study, this study, conducted in a lab in Boston, has not been peer-reviewed.
The U.S. Food and Drug Administration issued Emergency Use Authorization for the Johnson & Johnson vaccine – also known as the Janssen vaccine – in February. In the FDA’s initial data for the EUA, the single-shot vaccine was “85% effective in preventing severe/critical COVID-19 occurring at least 28 days after vaccination.”
The FDA authorized use of a Janssen booster dose in use in the U.S. in October. Both the primary dose and the booster are only authorized for adults 18 years or older. In April, the FDA recommended a pause in administration of the Johnson & Johnson vaccine in response to six cases of blood clots related to the shot, but lifted the pause less than two weeks later after the agency “determined that the available data show that the vaccine’s known and potential benefits outweigh its known and potential risks in individuals 18 years of age and older.”
Omicron became the dominant COVID variant in the U.S. around Christmas, according to data from the Centers for Disease Control. During the last week of 2021, COVID cases per capita for seniors were at their highest since last winter, with a rate of 236.8 per 100,000 for people aged 65-74 and 191.5 for people 75 years and older. Those numbers could also go up if more reports come in late to the CDC.
All adults are currently eligible for a COVID-19 vaccine as well as a booster if enough time has elapsed after their primary vaccine sequence. According to the CDC, people who got the single-shot Jannsen vaccine are eligible for a booster dose two months after their initial shot. Regardless of the initial sequence, any of the three authorized vaccines (Janssen, Pfizer-BioNTech and Moderna) can be used for a booster.
As for the other two authorized vaccines, people who got the Pfizer-BioNTech sequence can get a booster shot five months after their second dose, and those who got the Moderna sequence can get a booster six months after their second dose.