weakened immune systems

基本解释

CMV is a virus that can cause severe disease such as pneumonia or colitis in people with weakened immune systems, including organ transplant patients.
巨细胞病毒是一种病毒，它可导致伴免疫系统缺陷的人们（包括器官移植患者）患严重疾病，例如肺炎或大肠炎。
The CDC said the bacteria behind the outbreak — typhimurium — is common and not an unusually dangerous strain but that the elderly or those with weakened immune systems are more at risk.
疾病控制中心说，细菌隐藏在沙门氏菌感染爆发前一般不是非常危险的，但是对于老年人或者自身免疫系统功能低下的体弱群体，危险就增大了。
Researchers at the universities of Swansea and Milan believe the reason lies in the fact people with an internet addiction are more secluded, and as a result have weakened immune systems.
斯旺西大学和米兰大学的研究人员认为造成这一结果的原因是沉溺于网络的人更喜欢足不出户，因而导致免疫系统下降。

But Legionella bacteria can cause a form of pneumonia in people with weakened immune systems.
Fungi which don't often cause infections in people with healthy immune systems but can under some circumstances, and can be tremendous problems in patients that have weakened immune systems.
真菌在免疫系统健康的情况下通常,不引起感染,但在某些情况下也会感染,那就成了极大的问题,在免疫系统脆弱的病人体内
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