A striking impact on vaccine efficacy against variant B.1.351 has been observed. The efficacy of Novavax vaccine NVX-CoV2373 dropped from 96% to 48% (ref. 13); the efficacy of the Johnson & Johnson vaccine JNJ-78436735 decreased from 85% to 57% (ref. 14); and the efficacy of the Oxford–AstraZeneca vaccine ChAdOx1 dropped from 62% to 10% (ref. 15). Those drops were