Real-world data suggest 2 doses of Pfizer vaccine 70% effective at preventing hospitalization with Omicron variant

South African researchers released encouraging data on Tuesday based on real-world COVID-19 infections in the country during the current, fourth wave of coronavirus infections, driven almost entirely by the new Omicron variant. The preliminary analysis of data gathered by the insurer Discovery, which has not yet been peer-reviewed, shows the standard two-dose regimen of Pfizer-BioNTech's COVID-19 vaccine has been about 70% effective at preventing hospitalization over the last three weeks, as Omicron has swept across the country.

As both vaccinologists and the pharmaceutical companies that make the vaccines have said, the Omicron variant does appear to have a significant ability to evade the vaccines to cause infection. The data released on Tuesday suggests two shots of the Pfizer jab are only about 33% effective at preventing infection.

The findings mirror other preliminary research presented over the last week or so by Pfizer, and scientists in South Africa who have been testing the vaccines against the new variant.