是病毒毒性低缓解了.walgreens前几个月报道打疫苗后感染情况.BA.5已占美国covid病例近 90%.

https://weibo.com/ttarticle/x/m/show/id/2309404768238494941253?_wb_client_=1

https://www.nbcchicago.com/news/local/ba-5-symptoms-to-watch-for-and-more-information-about-americas-most-prevalent-covid-variant/2911927/