sanitation

The improvement of urban sanitation systems has significantly reduced the spread of waterborne diseases.

(Chinese) 城市公共卫生系统的改善显著减少了水源性疾病的传播。

Proper sanitation is difficult to maintain in overcrowded refugee camps without modern plumbing.

(Chinese) 在没有现代管道设施的拥挤难民营中，很难维持适当的卫生条件。