云南省大理州1992～2001年流行性乙型脑炎流行现状分析(摘要)

目的本文对云南省大理州12个县(市)1992～2001年流行性乙型脑炎(简称乙脑)的流行现状进行了分析.方法乙脑病例和疫苗接种率资料从大理州疾病预防控制中心收集,气象和稻田种植面积资料分别从大理州气象局和大理州土地局获得.统计学分析用STADA 6.0 软件进行.结果在这10年间,大理州共报道839例乙脑病例,其中死亡101例,发病率为0.91/10万～ 6.45/10万,死亡率为0.09/10万～ 0.52/10万, 病死率为7.92% ～16.47%.每年乙脑病例从4月出现,12月止,主要流行季节8至10月(占病例数的90.46%),9月为流行高峰 (占病例数的41.72%).大理州12县(市)都有乙脑病例分布,各县市发病率由高到低分别为宾川(7.3/10万)、祥云 (5.2/10万) 、漾濞 (5.2/10万) 、剑川(4.4/10万) 、巍山 (4.2/10万) 、洱源 (2.8/10万) 、大理市 (2.7/10万) 、弥渡(2.7/10万) 、南涧(2.7/10万) 、鹤庆 (1.8/10万) 、永平 (1.6/10万)和云龙(0.7/10万).从1997～2001年所报道的297例乙脑病例分析,1997年5～9岁为发病率最高年龄组,但是,随后几年,这种流行模式发生了变化,发病率的最高年龄组从5～9岁组逐渐迁移到大于15岁组.对于成人,发病率最高的人群为农民.乙脑病例中,男∶女比率为1.4∶ 1;死亡病例中,男∶女比率为4∶ 1.统计学分析发现各县市乙脑年发病率与年平均温度,年平均降雨量和水稻面积无明显相关,而乙脑疫苗接种是一种有效的预防控制方法.结论鉴于流行模式的改变,为防止乙脑的流行, 不仅要重视1～14岁年龄组乙脑疫苗的接种,而且要加强对15岁年龄组疫苗的预防接种.

Situational Analysis of Japanese Encephalitis in Dali Prefecture, Yunnan Province, China from 1992 to 2001

Objective The paper carried out the situational analysis of Japanese encephalitis (JE) in Dali Prefecture, Yunnan, China from 1992 to 2001. MethodJE cases had been collected from Center for Disease Control of Dali Prefecture and meteorlogical data and the areas of paddy field had been got from Meteorlogical Bureau of Dali Prefecture and Land Bureau of Dali Prefecture respectively. Data had been analyzed by STATA 6.0 software. ResultThe results showed that total 839 JE cases and 101 deaths had been reported for 10 years. The annual incidence rate varied from 0.91/100 000 to 6.45/100 000 population and the annual mortality rate was from 0.09/100 000 to 0.52/100 000 population with slightly decreased trend in both morbidity and mortality. The case fatality rate decreased from 15.84% in 1992 to 10% in 2001. The main epidemic season was from August to October and September was the peak month. In 1997, the highest proportion of cases was at children group aged 5～9 years, but there was some shift to older age during the study period. In 2001, the highest proportion of cases was among those aged equal or more than 15 years. Out of JE cases, the male to female ratio was 1.4 to 1 while it increased 4 to 1 among the deaths. Majority of adult cases was farmers. JE cases distributed all over Dali Prefecture. Binchuan, Xiangyun and Yangbin Counties had higher incidence rate of JE. We used multiple linear regressions to examine ecological factors and the incidence of JE in each county in each year. The results indicated that the average temperature, rainfall, and the areas of paddy field were not directly associated with the incidence rate of JE at the population level. Although we tried to control the coverage of JE vaccine in the analysis, this vaccine coverage data were only a proximate estimation, not came from the real coverage data. Moreover, some relevant factors such as number of pig farms or mosquito index were not available retrospectively. ConclusionTo overcome the problem of validity and availability of the data, prospective design is needed in order to answer the question about associate factors of JE diseases. Vaccinated JE vaccine is the main control measures. We should pay attention to vaccinating not only 1～14-year-old group, but also over 15- year-old group.