迷糊了。打疫苗反而減少保護？

But among patients who had received two doses of the vaccine, the variant’s prevalence rate was eight times higher than those unvaccinated – 5.4% versus 0.7%.

https://financialpost.com/pmn/business-pmn/south-african-variant-can-break-through-pfizer-vaccine-israeli-study-says?