I often get a cold, because I have weak immune system.

我经常感冒，因为我抵抗力差。

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The following acupressure points are effective for dealing with a condition that may be caused by a weak immune system.

下面的穴位是有效的免疫系统弱的处理与一个可能的条件所致。

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A relative said Abu Rahmeh had suffered from asthma since childhood and a family doctor said she had a weak immune system.

拉赫梅的一位亲戚说，她从小就患有哮喘病，而且一名家庭医生说她的免疫系统也很薄弱。

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However, patients with a weak immune system may not be able to do this - at which point the tuberculosis bacteria starts to spread in the lung.

BBC: TB link to ethnic minority poverty

Tuberculosis can lie dormant in a person for years and then strike when the immune system is weak.

BBC: NEWS | Health | Breathalyser detects tuberculosis

Who knows whether the symptoms are just being noticed once all the activities wind down or whether a child is simply fatigued enough that their immune system becomes a little weak.

CNN: Why do kids always get fevers on Sunday nights?