The COVID-19 vaccine from American drugmaker Pfizer and its German partner BioNTech appeared to avoid infecting the vast majority of recipients in Israel, offering the first real-world indication that coronavirus transmission can be curbed by immunization.
The vaccine, which was rolled out in a national immunization program that began on December 20, was 89.4 percent effective at preventing laboratory-confirmed infections, according to a copy of a draft publication. The companies and Israel’s Health Ministry worked together on the preliminary observational analysis, which has not yet been peer-reviewed.
The results are the latest in a series of positive data to emerge out of Israel, which has provided more COVID-19 vaccines per capita than anywhere else in the world. Nearly half of the population has had at least one dose of vaccine. Separately, Israeli authorities recently reported that the Pfizer-BioNTech shot was 99 percent effective at preventing deaths from the virus.
The early results on lab-confirmed infections are important because they show the vaccine may also prevent asymptomatic carriers (people who carry the virus and spread to others but do not show symptoms) from spreading the virus that causes COVID-19, something that hadn’t been clear so far. Stopping transmission in this way is a key factor as countries seek to lift contact restrictions and re-open economies.
Pfizer and BioNTech said they are working on a real-world analysis of data from Israel, which will be shared as soon as it’s complete.
Four-fifths of the virus cases in Israel during the time period of the study, which was from January 17 to February 6, were the more transmissible strain first identified in the UK. Israel’s vaccination drive began just before the so-called B.1.1.7 variant emerged, spiking infections and leading to a third lockdown on January 8.
Through February 6, about 27 percent of people aged 15 and older in Israel were fully vaccinated, with the Pfizer-BioNTech shot the only vaccine available in the country at the time.