1起伤寒副伤寒暴发的调查分析

目的　调查忠县伤寒副伤寒暴发的因素 ,为制定防制措施提供科学依据。方法　对患者进行统一个案调查并采样检测。结果　发现患者 961例 ,罹患率 3 68% ,其中血清学诊断 68例 (肥达反应阳性 ) ,病原学诊断 17例 ,其余病例根据临床表现 ,结合胶乳试验和流行病学史诊断 ;病例主要集中在场镇的 3所中小学 ,占 90 5 3% ;暴露因子分析显示 ,供应开水和未供应开水的学校罹患率分别为 0 2 1%、 2 6 2 8% ,两者发病差别有显著性 (P <0 0 0 5 ) ;常饮生水和不饮生水者罹患率分别为4 4 88%、 12 79% ,前者显著高于后者 (P <0 0 0 5 ) ;走读生和住校生罹患率分别为 17 5 6%、2 8 2 7% ,住校学生发病显著高于走读生 (P <0 0 0 5 ) ;饮用水中检出伤寒沙门菌。结论　饮水污染是本次伤寒副伤寒发生和流行的主要原因 ,生活密切接触传播也起着重要作用

Investigation on An Outbreak of Typhoid and Paratyphoid Fever in Chongqing Province

Objective To explore the risk factors of the outbreak of typhoid and to paratyphoid fever and to institute effective measures of control.Methods All cases were investigated.Some serum and stool specimens were collected from the cases andcontacts and were detected by Widals reaction test or Latex agglomeration test. Results 961 cases were reported and the attack rate was 3.68%.17 cases were confirmed by laboratory (10 cases were detected by Salmonella typhi and 7 by Salmonella bioserotype paratyphi A).66 serum specimens were detected by Widal's reaction test for the antibody.Others were for diagnosis clinically.90.53% of cases were reported from three primary and secondary schools.The results showed that there was a significant difference between boiled-water-supplied schools and others,with the attack rate of 0.21% and 26.28%(P<0.005)respectively.The attack rates of students frequently drinking umboiled water and students never drinking unboiled water,which were 44.88% and 12.79% respectively,also differed (P<0.005). The attack rate of boarders was higher than that of day students(P<0.005).Salmonella were isolated from the specimens of drinking water. Conclusions Contaminated water mainly contributed to the outbreak of typhoid fever and daily contact also played an important role.