针对COVID-19疫苗的感染保护在8个月后会减弱,但在严重结果的情况下持续一年以上,建议每年进行一次增强剂. COVID-19 vaccine protection against infection wanes after 8 months but lasts over a year against severe outcomes, with annual boosters advised.

在大约八个月后,防止感染的COVID-19疫苗保护率下降,降至50%-60%,但至少一年,特别是在多剂量的情况下,防止重病、住院和死亡的疫苗保护率仍然很高。 COVID-19 vaccine protection against infection declines after about eight months, dropping to 50%-60%, but remains strong against severe illness, hospitalization, and death for at least a year, especially with multiple doses. 建议采用年度助推器,但更频繁地接种疫苗可能会使免疫系统衰弱者受益。 Annual boosters are recommended, though more frequent vaccination may benefit those with weakened immune systems. 输血极为安全,美国只有四处致命的不匹配,超过1 000万次手术,尽管反应风险很少,但在紧急情况下使用O-阴性血液。 Blood transfusions are extremely safe, with only four fatal mismatches in the U.S. over 10 million procedures, and O-negative blood is used in emergencies despite rare reaction risks.