此文有两误：1）Omicron的通吃应该是指“感染过的和打了疫苗的都可以感染”，否则Delta也是通吃了。

2）流感疫苗的有效期也只有几个月，没有一年。A 2017 studyTrusted Source indicated that maximum immunity is achieved shortly following vaccination and decreases with each passing month. Therefore, if you get your vaccine in August, you may be more susceptible to infection late in the flu season, around February or March. 摘自 https://www.healthline.com/health/cold-flu/how-long-does-flu-shot-last#when-to-get-it