reinfection of newer portions

例句：

1. 1. The patient had to undergo a reinfection treatment.
   病人必须接受再感染治疗。
2. 2. The virus can cause reinfection after the initial infection has passed.
   病毒可以在初次感染后引起再感染。
3. 3.Doctors are trying to prevent reinfection in hospitals.
   医生们正试图在医院防止再感染。