@Lucypurr12 By official rules? Depends who you are and where you live, maybe never.
Israel has been giving them to 60+ and HCW four months after the third dose. US gives a 4th dose to immunocompromised six months after third.
@Lucypurr12按官方规定？取决于你是谁，住在哪里，也许永远不会。
以色列在第三次给药四个月后一直给他们注射60+和HCW。美国在第三次注射六个月后给免疫功能低下的患者第四次注射。