En el primer estudio que caracteriza la epidemiología de COVID-19...Leer más
The COVID-19 death rate among people who got the Johnson & Johnson vaccine was more than double the rate of other vaccinated Americans during the Omicron wave, according to the latest CDC data.
During the week of Jan. 8, coronavirus-related deaths among Johnson & Johnson vaccine recipients reached more than five out of every 100,000 people, CBS News reported. For those who got the Pfizer or Moderna vaccines, the rate was around two deaths per 100,000 people.
Both numbers were a fraction of the rate of COVID-19 deaths for unvaccinated Americans, which was close to 20 per 100,000 people.
Among Americans who received a booster shot, those who first got a Johnson & Johnson shot had higher rates of COVID-19 deaths than those who started with doses of the Pfizer or Moderna vaccines, the CDC data shows.
At the same time, the rates of COVID-19 breakthrough cases were similar or lower for Johnson & Johnson vaccine recipients, compared to those who got the other vaccines.
“The CDC data adds to the growing body of evidence indicating the Johnson & Johnson vaccine provides durable protection against breakthrough infection and hospitalization,” Jake Sargent, a spokesperson for the company, told CBS News.
The data isn’t adjusted for a range of things that can affect direct comparisons between the vaccines, CBS News reported, such as other medical conditions or the time since vaccination.
Researchers are trying to understand the differences among the COVID-19 vaccines and how the immune response may vary in the real world over time. Although the Johnson & Johnson vaccine appeared to offer less protection during the Delta and Omicron waves, studies have suggested that the shot offers longer-lasting protection.
During the Delta wave, for instance, the Johnson & Johnson vaccine was 81% effective against hospitalizations for “at least 180 days after vaccination,” according to a study published in JAMA Network Open in mid-March. Other estimates have found that the strength of the Pfizer and Moderna vaccines appeared to wane sooner than the strength of the Johnson & Johnson vaccine.
“The J&J vaccine is different in that initially, the antibody responses are quite a bit lower than the mRNA vaccines. But those responses actually are maintained very well over time, even increase a little bit,” Dan Barouch, MD, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center, told CBS News.
In December 2021, Johnson & Johnson published research from Barouch’s team, which showed that people who received its booster shot had higher antibody levels after 4 weeks, compared to those who only received the Pfizer shot. The study also found that the vaccine generated larger increases in T cells as part of the immune response.
“The T-cell responses appear to be less dependent on the variants,” Barouch said. “So that T-cell response probably has a particularly important role in protecting against severe disease, probably with variants that largely escape antibodies.”
Few studies have been able to directly measure and compare the immune responses of the different vaccines, including the early response of neutralizing antibodies and the long-lasting response of T cells and B cells.
“The only way to really compare immune responses to different vaccines is to really do them all in the same lab, at the same lab truly head-to-head. We can’t compare a Pfizer clinical trial paper with the Moderna clinical trial paper with the J&J clinical trial paper,” Shane Crotty, PhD, a professor at the La Jolla Institute for Immunology, told CBS News.
This month, Crotty’s research team released a preprint study, which hasn’t yet been peer-reviewed, that looked at the immune responses triggered by the first shots of the Johnson & Johnson, Moderna, Pfizer, and Novavax vaccines after 6 months. They found that the Johnson & Johnson vaccine “was not the strongest immunogen by any measurement,” but its T-cell, B-cell, and antibody responses were “relatively stable” over 6 months.
The FDA and its vaccine advisory group will meet next week to discuss extra booster doses, as well as the process for selecting COVID-19 vaccine strains to address current and emerging variants.
Créditos: Comité científico Covid