This week, each company asked the FDA to authorize additional boosters — Pfizer for people over 65, and Moderna for all adults. At the same time, a study published Thursday in the journal JAMA Network Open estimated that a single Johnson & Johnson shot was 76 percent effective at preventing Covid infection and 81 percent for hospitalizations for at least 180 days.

The study aligns with data from the Centers for Disease Control and Prevention showing that from late December through Feb. 19 (the most recent data available), the weekly rate of breakthrough cases was lowest among people who got the J&J shot. The rate of Covid deaths among J&J recipients, however, was a bit higher than among those who got mRNA vaccines through Jan. 29. 

Together, this evidence suggests the J&J shot might have an edge in durability over the two mRNA vaccines. None of the more than 422,000 J&J recipients in the recent study got boosters during the research period, which ended in August.

J&J’s Covid vaccine shows promising long-term durability (nbcnews.com)