大规模的新冠疫苗接种开始了。给新冠流行早日得到控制,日常生活早日恢复正常带来希望。同时也引起一些担心。有些是因为对此病毒的特性,mRNA 疫苗 的了解不足。这需要科学界继续努力。有些是因为民众对基本的病毒感染,免疫反应知之有限,加上媒体上一些有意无意的误导。举几个例子:
1, 有人担心,疫苗接种后,抗体只能存在几个月,没有长期保护作用。其实,任何一种特异性抗体的半衰期也就是几周。产生,分泌此抗体的浆细胞,在没有抗原和其它辅助因子刺激下,不久就休眠了。但是记忆细胞会在抗原再次进入时被激活,产生抗体。
2,常常有人把疫苗接种后,局部的红肿酸疼,体温升高等都说成但是接种的副作用。其实这些正是疫苗接种的效果。
谢谢来访。
People who recover from COVID-19 sometimes later test positive for SARS-CoV-2, suggesting their immune systems could not ward off a second attack by the coronavirus or that they have a lingering infection. A study now hints at a different explanation in which the virus hides in an unexpected place. The work, only reported in a preprint, suggests the pandemic pathogen takes a page from HIV and other retroviruses and integrates its genetic code—but, importantly, just parts of it—into people’s chromosomes. The phenomenon, if true and frequent, could have profound implications that range from false signals of active infection to misleading results from COVID-19 treatment studies.
The current study only showed this integration in a lab dish, although it also cites published sequence data from humans infected with SARS-CoV-2 that suggest it has happened. The authors emphasize that their results don’t imply that SARS-CoV-2 establishes permanent genetic residence in human cells to keep pumping out new copies, as HIV does.