Promising data in Israel's race to defeat pandemic Weizmann Institute researcher Eran Segal says among the first fully-vaccinated group there was a 53% reduction in new cases, a 39% decline in hospitalizations and a 31% drop in severe illnesses from mid-January until Feb. 6 Reuters | Published: 02.10.21 , 09:47 Israel's swift vaccination rollout has made it the largest real-world study of Pfizer Inc's COVID-19 vaccine. Results are trickling in, and they are promising. More than half of eligible Israelis - about 3.5 million people - have now been fully or partially vaccinated. Older and at-risk groups, the first to be inoculated, are seeing a dramatic drop in illnesses.