正確。依據2021/03/16的《新英格蘭醫學期刊/The New England Journal of Medicine》報告,一項約兩千人,牛津疫苗在南非當地,對南非變異株(B.1.351)的保護力僅約10,4%。南非政府據此宣布停止施打牛津疫苗
資料佐證
Shabir A. Madhi, Ph.D., Vicky Baillie, Ph.D., Clare L. Cutland, Ph.D., Merryn Voysey, D.Phil., Anthonet L. Koen, M.B., B.Ch., Lee Fairlie, F.C.Paeds., Sherman D. Padayachee, M.B., Ch.B., Keertan Dheda, Ph.D., Shaun L. Barnabas, Ph.D., Qasim E. Bhorat, M.Sc., Carmen Briner, M.B., B.Ch., Gaurav Kwatra, Ph.D., et al., for the NGS-SA Group Wits–VIDA COVID Group (2021) Efficacy of the ChAdOx1 nCoV-19 Covid-19 Vaccine against the B.1.351 Variant. The New England Journal of Medicine. DOI: 10.1056/NEJMoa2102214