The four problems in question are how to prevent various epidemics, alleviate existing ailments, conquer malignant tumors, and respond to the emergence of new diseases respectively.

• 正在讨论中的四个问题分别是：怎样预防各种流行病，怎样减轻现有的疾病，怎样攻克恶性肿瘤和怎样应付新出现的疾病。