According to
an analysis carried out by Public Health England, two doses of the Pfizer-BioNTech vaccine appeared to be about 88 percent effective against symptomatic disease and 96 percent effective against hospitalization with the delta variant.
The same study suggested that the vaccine was approximately 80 percent effective against preventing infection from the delta variant. Scientists came to this conclusion after analyzing 14,019 people with an infection, 166 of whom were hospitalized, in England.
Vaccines had a protective effect against infections with delta and hospital cases were milder, the study found.