Real-World Study: Pfizer Vaccine 94 Percent Effective

A study of over half a million inoculated people found that two doses of the Pfizer vaccine is 94% effective in preventing symptomatic COVID-19 in all age groups.

According to CBS News, results of the Israeli study in collaboration with experts at Harvard University were published Wednesday in the New England Journal of Medicine.

“The study provides the first large-scale peer-reviewed evaluation of the effectiveness of a COVID-19 vaccine in a nationwide mass-vaccination setting,” said researchers at the Chalit Research Institute in Israel.

Researchers also found that even after one dose, the vaccine helped prevent serious illness and death. While most data about vaccine efficacy has been gathered from controlled clinical trials, Israel’s speed in vaccine rollout provided the ideal opportunity to evaluate real-world statistics.

The total study involved 1.2 million people, according to CBS News, and demonstrated that one shot of the COVID-19 vaccine provides 57% protection against symptomatic infections after two weeks. One shot also was 62% effective in preventing severe illness. That number rose to 92% after the second dose.

At the time of the study, the dominant strain of the virus was the U.K. variant, so the results reveal that the Pfizer vaccine is effective against that mutation. Pfizer and BioNTech announced Thursday that they have begun an evaluation on the safety and benefit of a third COVID-19 vaccine to protect against emerging variants of the virus.