Live Update 
From the Liveblog of
Thursday, October 21, 2021
From the Liveblog of
Thursday, October 21, 2021
3rd dose of Pfizer vaccine 95.6% effective against Delta — phase 3 trial result
A third dose of the vaccine against COVID-19 developed by Pfizer-BioNTech is 95.6% effective against symptomatic infection, according to a study by the makers published today.
The clinical phase 3 trial with “10,000 participants 16 years of age and older” showed “a relative vaccine efficacy of 95.6 percent against disease during a period when Delta was the prevalent strain,” the companies say in a statement.
