为应对Delta等变异株及突破性感染，不同技术路线序贯免疫策略提供了一种非常高效的解决方案 。值得注意的是，无论是完整接种2剂疫苗，还是接种第3剂加强针，BNT162b2 mRNA疫苗在针对原始毒株和变异株（尤其是Delta变异株）上均有优异“战绩” 。mRNA疫苗作为序贯免疫加强针，可产生更好的免疫应答反应，或许是一种更佳的疫苗接种策略 。
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【新冠疫苗|第三针新冠疫苗，我们应该如何选？】