Abstract: Objective To investigate the reason and the appropriateness of emergency response measures on tuberculosis（TB）aggregation in school.  Methods Data of 10 TB aggregations in school of Shaanxi province since 2006 to 2012 were collected, which were from epidemic situation report, case diagnosis, individual basic information, close contactors screening, protection of infected students, healthy education, emergency response situation, the final report, the occurrence of subsequent cases, et al.  Results The shortest patient delay of the first visit case was 15 days in Chang’an College, and the longest was 64 days in the high school of Cheng country. The average patient delay was 26.7（267/10）days. The shortest diagnostic delay was 20 days in the high school of Cheng country, and the longest was 156 days in the junior high school of Xun’yi country. The average diagnostic delay was 31.2（312/10）days. After the diagnosis, the interval for close contacts screening lasted from 2 days to 403 days with an average of 121.1（1211/10） days. The lowest PPD positive rate of close contacts in these ten epidemics was 49.5%（229/463）in the junior high school of Tibet, and the highest was 100.0%（43/43）in Chang’an College, with an average of 59.2%（1128/1906）. The lowest PPD positive rate of general contacts was 9.5%（18/189） in the junior high school of Xun’yi country, and the highest was 56.4%（1055/1871）in Chang’an College, with an average of 34.2%（3861/11 282）. The difference between the average PPD positive rates of close contact and general contact was statistical significant（χ²=431.9，P＜0.001）. The lowest attack rate of close contacts was 3.6%（25/698）in the high school of Cheng country, and the highest was 37.2%（16/43）in Chang’an College, with an average of 8.9%（174/1963）.  Conclusion Lack of timely detection, isolation and treatment for the sources of infection and no timely and effective screening of exposed population are the main reasons of TB aggregation.

Key words: Tuberculosis, pulmonary/transmission, Tuberculosis, pulmonary/epidemiology, Students, Shaanxi province