The resistance to illness among children with Down's is poor, and they easily catch infections. Add to this that many of those with Down's suffer compound illnesses, with half having congenital heart problems, with others possibly having irregularly shaped intestines, leukemia, abnormal functioning of the thyroid, and other conditions, which can easily be fatal.
唐氏症兒抵抗力差，易受細菌感染，再加上患者常伴有一些併發症，其中二分之一有先天性心臟病，其他還可能有腸胃道先天畸型、白血病、甲狀腺功能異常等等病症，因而容易導致死亡。