Pfizer, Moderna COVID-19 vaccines just 66% effective against Delta variant: Study

As per a study published by a large number of US health workers, messenger RNA Covid vaccines are just 66 percent effective against the highly contagious Delta variant. These vaccines include Pfizer and Moderna that were said to be 91 percent effective against other variants of the infection. The real-world performance of the two vaccines is being examined by the Centers for Disease Control and Prevention.