内蒙古自治区传染性非典型肺炎疫情趋势分析

目的：分析内蒙古自治区传染性非典型肺炎严重急性呼吸综合征(SARS)]流行情况。方法：利用法定报告传染病资料进行统计分析。结果：2003年3月27日内蒙古自治区报告首例SARS病例，截止到5月20日，全区累计报告446例(诊断病例287例、疑似病例159例)。累计报告出院61例(诊断56例、疑似5例)，排除131例(诊断10例、疑似121例)，诊断病例死亡25例，病死率为8．7％。累计报告病例分布在9个盟(市)30个旗(县)。按发病时间统计，发病集中在4月13—29日，占总数的67．7％。4月24日开始发病呈波动性下降，5月3—8日每日平均发病数为5．3例，5月9日以后每日平均发病数为0．3例。结论：内蒙古自治区SARS流行过程大致可以分为3个时期：第一时期即3月18日至4月15日，为输入性感染期，发病呈缓慢上升，涉及6个盟(市)14个旗(县)，特点是家庭聚集性感染；第二时期即4月16—28日，为继发性感染期，发病大幅度上升，涉及10个盟(市)24个旗(县)，特点是医院成为继发性感染的重要来源；第三时期即4月29日至今，为散发感染期，发病有小的波峰，涉及到10个盟(市)、38个旗(县)，特点是无接触史者发病比例高，但未形成明显的传播链条。

Analysis on the trend of severe acute respiratory syndrome epidemic in Inner Mongolian Autonomous Region

Objective To analyse the severe acute respiratory syndrome (SARS) epidemics in Inner Mongolian Autonomous Region and to provide scientific basis for prevention and control strategies against it. Methods Data from legal communicable diseases surveillance reporting system was analyzed epidemiologically. Results The first SARS case was reported in Inner Mongolian Autonomous Region on March 27,2003.Up to May 20,there were 446 cumulative SARS cases in the whole region (with 287 confirmed cases and 159 suspected cases) and 61 cumulative recovered cases had been discharged from the hospitals (56 confirmed cases and 5 suspected cases). Another 131 cases were excluded the original diagnoses of SARS inclluding 10 confirmed cases and 121 suspected cases. 25 confirmed cases died with a mortality rate of 8.7%. Cumulatively, the number of reported cases were distributed in 30 counties in 9 prefectures. Statistical analysis on time sequence of the occurrence of cases showed that majority ( 67.7% of the total) of the cases concentrated in between April 13 and April 29. The number of cases had started to decrease since April 24 with an average of 5.3 cases per day between May 3 and May 8 and an average of 0.3 cases per day between May 9 and today. Conclusions SARS epidemics in our region could be divided into three phases. The first phase fell in between March 18 and April 15 with the first case being imported, the number of cases rose sharply, covering 14 counties in 6 prefectures, having a feature of family clustering. The second phase was from April 16 to April 28, with the appearance of secondary infection, having sharp rise of the cases and spreading to 24 counties in 10 prefectures. One of the major features was that hospitals had become the important sources of secondary infection. Finally, the third phase was between April 29 and May 20, with small wave crests of cases, spreading to 38 counties in 10 prefectures wiht a high proportion of cases with no history of direct contact with diagnosed SARS patients. Thus, no obvious transmission chain was noticed at this phase.