weakened immune system 抵抗力弱

weakened immune system
繁：抵抗力弱
简：抵抗力弱

前日完成世衞專家會議從埃及返港的中大內科及藥物治療學系教授許樹昌表示，中東新沙士患者九成半有長期病患，抵抗力弱，感染後病情嚴重及增死亡率。

染新沙士九成五長期病患（2013年6月23日）。東方日報，取自 http://orientaldaily.on.cc/cnt/news/20130623/00176_041.html

According to the WHO, the virus appears to hit most severely people with weakened immune systems, older people, and those with chronic diseases such as diabetes, cancer and lung disease.

How to avoid the Mers virus, according to health officials. (2015, May 30). South China Morning Post. Retrieved from http://www.scmp.com/news/article/1813120/how-avoid-mers-virus-according-health-officials