Three studies in the United States have suggested that COVID-19 vaccines offer strong protection against hospitalization and death, even amid the spread of the highly transmissible Delta variant. However, the protection extended by the vaccines seems to be waning among older individuals, particularly among those aged 75 years and older.

Data on hospital admissions from nine states during the period when the Delta variant was dominating also indicated that the Moderna vaccine was comparatively more effective at preventing hospitalizations among individuals of all ages compared to the Pfizer/BioNTech or Johnson & Johnson COVID-19 vaccines. In that study involving over 32,000 visits to urgent care centers, emergency rooms and hospitals, the Moderna vaccine was found to be 95% effective at preventing hospitalization, while the Pfizer vaccine was 80% effective and the J&J vaccine was 60% effective… (Reuters, September 10, 2021)