疾病已使他不能生育。

The disease had made him sterile.

年纪大本身不是一种疾病。

Old age itself is not a disease.

人们努力控制这种疾病。

Efforts were made to check the disease.

疾病成为调查的对象。

Disease became the object of investigation.

疾病和体弱紧密相关。

Disease and lack of fitness are closely related.