Thursday, December 07, 2023
Real-world data demonstrated 92% vaccine effectiveness against hospitalisations due to the Delta variant 
New data from Public Health England (PHE) demonstrated COVID-19 Vaccine AstraZeneca offers high levels of protection against the Delta variant (B.1.617.2; formerly the ‘Indian’ variant).
Real world data from PHE, published as a pre-print, demonstrated two doses of COVID-19 Vaccine AstraZeneca are 92% effective against hospitalisation due to the Delta variant and showed no deaths among those vaccinated. The vaccine also showed a high level of effectiveness against the Alpha variant (B.1.1.7; formerly the ‘Kent’ variant) with an 86% reduction of hospitalisations and no deaths reported.
The data suggest that vaccine effectiveness against milder symptomatic disease, although significant, was lower. Vaccine effectiveness against symptomatic disease was 74% against the Alpha variant and 64% against the Delta variant.
The higher efficacy against severe disease and hospitalisation is supported by recent data showing strong T-cell response to COVID-19 Vaccine AstraZeneca, which should correlate with high and durable protection.1
Mene Pangalos, Executive Vice President, BioPharmaceuticals R&D, said: “This real world evidence shows that COVID-19 Vaccine AstraZeneca provides a high level of protection against the Delta variant, which is currently a critical area of concern given its rapid transmission. The data show that the vaccine will continue to have a significant impact around the world given that it continues to account for the overwhelming majority of supplies to India and the COVAX facility.”
The analysis included 14,019 cases of the Delta variant – 166 of whom were hospitalised – between 12 April and 4 June, looking at emergency hospital admissions in England.
This real world evidence against the Delta variant is based on limited follow up after the second dose which could impact the effectiveness estimate.
The Delta variant is a key contributor to the current wave of infection in the Indian subcontinent and beyond. It has recently replaced the Alpha variant as the dominant strain in Scotland and is responsible for a notable increase in cases in the United Kingdom. The WHO Strategic Advisory Group of Experts on Immunization (SAGE) has recommended COVID-19 Vaccine AstraZeneca in countries where new variants, like the Delta variant of concern, are prevalent.
