Abstract：Objective To investigate the scale and epidemiological features of a mumps outbreak so as to understand the protective effect of mumps vaccine. Methods A mumps outbreak was reported in a primary school in Wulong County, and all the students of the school were involved as the objects of this study. By formulating the definition of cases and collecting the immunization information of these cases, descriptive analysis of epidemiological characteristics and retrospective cohort study were performed to calculate the protective effect of mumps vaccine. Results A total of 87 cases with clinical diagnosis were collected, and no severe cases and deaths found. The attack rate of the students was 1.51%, including 42 boys, and no statistically signiciant difference was observed in the attack rate between genders (χ2=0.59, P=0.442). The ages of the cases were 8 years old, accounting for 58.62%. Most of the cases were distributed in the classes 1-4 of second grade, which were on the 4th floor of teaching building A, and the attack rates of the classes 1-4 were 28.17%, 39.44%, 5.63% and 12.12% respectively. The epidemic curve showed an identical exposure duration. The vaccination rate of mumps-containing vaccines in the classes 1-4 of second grade was 45.16%, there was a statistically significant difference in the incidence rate of mumps among different vaccination status(χ2=4.078,P=0.0435). The total efficacy of mumps-containing vaccines was 43.00%. 5-6 years after vaccination, the protective efficacy of the last dose of mumps-containing vaccines was 56.00%, and there was a statistically significant difference in the incidence rate of mumps between students with inoculation interval up to 5-6 years and ones without vaccination history(χ2=5.60,P=0.02). Conclusions This is an epidemic outbreak caused by mumps virus, and the most possible reasons for the outbreak may include that a large number of students exercise and learntogether, the ventilation of classrooms is poor, the school still holds a rally during the early stage of mumps epidemic, and a long interval of inoculation. The mumps-containing vaccines have a definite protective efficacy; and hence, we recommend inoculating the mumps-containing vaccine among the local susceptible population so as to increase the vaccination rate and establish the herd immunity.
周春碚, 肖达勇, 夏宇, 孙毅, 申涛, 程颖, 王亮, 李勤. 重庆市武隆县某小学流行性腮腺炎暴发疫情调查[J]. 实用预防医学, 2017, 24(7): 844-847.
ZHOU Chun-bei, XIAO Da-yong, XIA Yu, SUN Yi, SHEN Tao, CHENG Ying, WANG Liang, LI Qin. Epidemiological survey of a mumps outbreak in a primary school in Wulong County, Chongqing. , 2017, 24(7): 844-847.
2017, Vol. 24 
