Vaccine effectiveness high against severe Delta-caused COVID-19A 17-study literature review looking at vaccine effectiveness (VE) during the Delta (B1617.2) variant shows a pooled VE of 90.9% versus hospitalization with a 75.7% and 63.1% VE against symptomatic and asymptomatic infection, respectively.The results, published yesterday in Eurosurveillance, were based on studies collected until Aug 25.
Some studies looked at VE against Delta and Alpha (B117) using sequenced samples, while others looked at VE from time periods where Delta or Alpha was the dominant strain without sequencing samples.
Asymptomatic infections (2 studies), symptomatic infections (9), the compound outcome of severe disease and hospitalization (3), and hospitalization