灭活疫苗的免疫原性不够强,在老年人诱导不出足以抗衡新冠病毒的抗体。
俺以前写的 https://bbs.wenxuecity.com/health/946237.html
参见
https://www.nature.com/articles/s41577-020-00434-6
killed virus vaccines sometimes require the inclusion of an adjuvant and repeated administration for full efficacy