Before this gets out of hand... The first two weeks after a vaccine will include pre-vaccine infections PLUS the immune system takes some time. So "one-dose efficacy" can't be calculated without that info. A reporter can track down author's reported response? via @supermarioelia https://twitter.com/DrEricDing/status/1390107362485211136

(I still wish he had a proper trial on dose-sparing strategies so we'd have longer-term data, too but...) Let's not needlessly panic people who are in countries that use this strategy. But GOOD REMINDER: the first week or two after vaccination isn't post-vaccination at all.

See more here: https://twitter.com/zchagla/status/1390351418549276676

Speaking of, the study also does find that the (Pfizer-BioNTech) vaccines were 97.4% (CI:92.2–99.5) effective against preventing severe outcomes (hospitalization and death) for all breakthrough cases, including for B.1.351 variant.