甘肃省2004-2017年流行性乙型脑炎发病及流行特征

Incidence trend and prevalence status of Japanese encephalitis in Gansu province, 2004–2017

目的了解甘肃省流行性乙型脑炎(简称乙脑)发病及流行特征变化趋势,为今后乙脑防控工作提供依据。方法收集整理2004-2017年甘肃省既往乙脑发病数据,采用描述流行病学分析甘肃省乙脑发病及流行特征变化趋势。结果 2004-2017年甘肃省共报告乙脑病例1 018例。随着乙脑疫苗的使用,乙脑发病高峰间隔由3~4年改变为9~10年,地区分布从甘肃省东南部向中部蔓延,高发年龄由<14岁儿童转变成人,所占比例由2004年的69.56%下降至2017年的4.70%(χ2趋势=215.776,P=0.000);15~39岁乙脑病例所占比例无明显变化(χ2趋势=1.29,P=0.256),平均占比为23.97%;≥40岁乙脑病例所占比例由2004年的6.52%上升至2017年的70.72%(χ2趋势=148.466,P=0.000)。职业分布由以农民、学生、幼托及散居儿童为主转变为以农民为主(χ2趋势=178.646,P=0.000)。结论甘肃省乙脑高发地区较以往有所扩大,儿童乙脑发病得到了明显控制,成人乙脑发病显著增加。

Objective To analyze variations in incidence and prevalence characteristics of Japanese encephalitis(JE) in Gansu province between 2004 and 2017 for providing evidences to the prevention and control of JE. Methods We collected data on JE in Gansu province from National Notifiable Disease Information Reporting System and analyzed the data with descriptive epidemiology methods. Results Totally 1 018 JE cases were reported during the period in the province. With vaccinations of JE vaccine, the peak incidence interval of JE changed from 3 – 4 years to 9 – 10 years;the JE epidemic area extended from the southeastern to the central region of the province;the population with high incidence shifted from the children under 14 years old to the adults, with a decreased proportion of the reported cases less than 14 years old from 69.56% in 2004 to 4.70% in 2017(χ2trend = 215.766, P < 0.001). The proportion of the JE cases aged 15 – 39 years old showed no significant variation(χ2trend = 1.29,P = 0.256), with an average ratio of 23.97%. The proportion of JE cases aged40 years and above increased from 6.52% in 2004 to 70.72% in 2017(χ2trend = 148.466, P < 0.001). The majority of the JE cases shifted from farmers, students, small and scattered living children to farmers(χ2trend = 178.646,P < 0.001).Conclusion The area with high incidence of JE extended and JE epidemic was well controlled among children but not in the adults in Gansu province between 2004 and 2017.