Efficacy Of RNA Covid Vaccines, Moderna And Pfizer, Reduced To 66%

Pfizer and Moderna, the RNA Covid vaccines, are only 66% effective against the Delta variant, a study published by several US health workers stated. The study previously showed 91% efficacy from December 14, 2020, to April 10, 2021. However, the spread of the delta variant dropped the potency to 66%. "The sustained two-thirds reduction in infection risk underscores the continued importance and benefits of COVID-19 vaccination," the authors said.