My friend is confused

Friend already got his booster shot due to his old age. 

This morning he is confused about a friend's daughter. She caught COVID19 twice after she is fully vaccinated. And her unvaccinated husband is fine. How could this happen?

People are different. My family never took flu shots and never v

你确定是在完成疫苗接种后两次感染新冠？那这真是闻所未闻

如果是真的，那就说明不但疫苗无用，自然免疫也无用。

当然，还有一种可能是，此女存在特殊的免疫功能问题，如果是这样，那也赖不上疫苗了。

熟人打了2针疫苗，一个多月前得了，家人没有（都打过疫苗），他恢复了，没去看病，症状还是很明显的

never visited doctors for flu.

看来打过疫苗的得病毒后的传染性很低。如果全都打过疫苗，病毒就失去传染性了。