It has been varied in opinions in our country about investigation in public health affairs. How far should one invest? All has been deeply concerned. In our study, the tuberculosis patients had been constantly followed up by public health department. With this simple monitoring system on patients number, age and distribution, and the cooperation of staffs in the hospital, we accidentally detected one tuberculosis endemic event in Shiu-Lin rural village, Hualien, Taiwan. This exciting result give us a positive answer to those concern, which we have mentioned before.