Nine study findings on COVID-19 vaccines — including how effective they are in younger children and pregnant women, as well as which vaccine produces the highest antibody levels — as reported by Becker's Hospital Review since the end of August:
- Decreases in vaccine efficacy are driven more by the delta variant and behavioral changes than the vaccine itself, according to a study published on the preprint server MedRxiv that included 8.8 million New Yorkers.
- Six months after a second dose of a Pfizer COVID-19 vaccine, men had substantially lower levels of neutralizing antibodies than women in a study published in The New England Journal of Medicine.
- Pfizer's COVID-19 vaccine was 90 percent effective in preventing hospitalization and death for at least six months in a study published in The Lancet.
- AstraZeneca's COVID-19 vaccine was 74 percent effective at preventing symptomatic disease in its phase 3 U.S. clinical trial, according to a study released in The New England Journal of Medicine.
- Johnson & Johnson said that a two-dose regimen for its COVID-19 vaccine provided 94 percent protection against symptomatic infection in a study of 390,000 people.
- Pfizer said its COVID-19 vaccine is safe and effective in children ages 5 to 11, according to data from a phase ⅔ study that included 2,268 participants.
- Moderna's COVID-19 vaccine was the most effective at protecting against hospitalization in a CDC study.
- Pfizer's COVID-19 vaccine's effectiveness in pregnant women is similar to the effectiveness observed in the general population, at 96 percent effective for any infection and 97 percent effective for symptomatic infection after the second dose, according to an Israeli study published in Nature.
- Moderna's COVID-19 vaccine creates antibody levels more than twice as high as Pfizer's, according to a study published in JAMA that examined 2,499 healthcare workers in Belgium.