中国2005--2011年人狂犬病不同地区季节分布特征研究

Study on the seasonal distribution of human rabies in different regions of China

目的用简单定量方法描述中国不同地区狂犬病发病季节分布特征和规律，分析地理位置对其影响，为狂犬病风险评估、疫情预测提供依据。方法以全国法定传染病报告系统中2005--2011年29个省份报告的17800例临床与实验室确诊狂犬病病例为研究对象，从国家地理信息中心获得各省地理经纬度资料，利用Excel2003软件绘制季节分布曲线，利用SPSS18．0软件计算季节分布曲线的第25百分位数（P25）、P50、P75、四分位数间距（Q）和峰度，并分别分析P25、峰度与纬度的线性相关关系。结果全国狂犬病发病以2月为低点，夏、秋季为发病高峰，峰值在8月。各省份狂犬病发病季节分布曲线的P25、P50、P75、Q和峰度不同，纬度越高地区的P25越大，Q值越小，峰度越大；在年均报告病例数〉100例的9个省份，P25、峰度与纬度间的相关系数r值分别为0．9342、0．8528（P〈O．05）。结论中国狂犬病发病具有季节性，且存在地理差异和规律性，纬度越高地区季节性特征越明显。

Objective Using simple quantitative methods to describe the seasonal distribution of rabies in different provinces of China and to analyze how it was influenced by geographical settings, to provide evidence for risk assessment and prediction of potential epidemics of rabies. Methods A total number of 17 800 clinical and laboratory confirmed rabies cases, reported by 29 provinces, from 2005 to 2011 and related data were collected from National Disease Reporting Information System. Data on related latitudes and longitudes of different provinces were obtained from the National Geographic Information Center. Excel 2003 was used to draw the national and provincial seasonal distribution curves while SPSS 18.0 was used to calculate parameters as P25, Ps0, P75, inter-quartile range Q and kurtosis so as analyze the linear correlation between P25, kurtosis and the latitude of different provinces respectively. Results The nation-wide incidence of rabies was low in February. The peaks fell in summer and autumn, especially in August. Seasonal distribution curves of P25, P50, P75, inter-quartile range （Q） and kurtosis were different among provinces. Compared to the low latitude areas, high latitude areas had higher P25, smaller Q and higher kurtosis. In 9 provinces where the annual reported number of cases more than 100, the related coefficients （r） between latitude and both P25, kurtosis were 0.9342 and 0.8528 respectively （P〈0.05）. Conclusion There was a distinct seasonality of rabies occurrence in China which was correlated to the geographical settings which was more obvious in the higher latitude areas.