基于发热症状监测系统的甲型副伤寒疾病负担分析

Burden of disease regarding paratyphoid fever A-- based on the Syndromic Surveillance System on Fever

目的评估云南省玉溪市红塔区2008年5月1日至2009年4月30日甲型副伤寒的流行病学负担。方法在建立基于全人群的发热症状监测系统基础上，分别调查和测算红塔区发热病例的就诊率，就诊病例采样率，样本检测率，检测方法灵敏度和实验室确诊病例报告率等，根据食源型疾病的疾病负担金字塔模型对当地伤寒、副伤寒的实际发病数进行估算和分析。结果发热症状监测系统一年内共监测红塔区发热病例6642例，采样并检测6570例，采样率为98．92％，检测率为100％。确诊居住在红塔区的甲型副伤寒阳性病例354例。调查发现发热病例就诊率为73．53％，其中10岁以下儿童就诊率为100％。依据参考文献假定血培养法检测甲型副伤寒的灵敏度为70％，病例网络报告率为90％，经倍数校正后估算红塔区甲型副伤寒年发病数为965例（95％CI：745～2284），年发病率为220．33／10万（95％CI：170．1～521．4），其中发病率最高的年龄组为15～44岁组（318．27／10万）。结论玉溪市红塔区甲型副伤寒处于高流行状态，15～44岁组为高发人群，应采取有针对性的防治措施以减缓甲型副伤寒的高发态势。

Objective To evaluate the burden of paratyphoid fever A in Hongta district, Yuxi city, Yunnan province from May 1,2008 to April 30, 2009 so as to provide information for the development of comprehensive intervention measures. Methods Based on the Fever Syndromic Surveillance System, information as attendance rate of patients with fever, rate of patients being sampled, laboratory testing rate, sensitivity on the detection of blood culture and the rate of case reporting etc. were calculated. According to the pyramid model of food-borne disease on disease burden, the local actual incidence of paratyphoid fever A was estimated and analyzed. Results Under the Fever Syndromic Surveillance System, there were 6642 fever cases being detected, among whom 6570 cases were sampled and undergone testing, with the sampling rate as 98.92% and all the samples received laboratory testing. There were 354 positive cases of paratyphoid fever A reported, all from the Hongta district. Data showed that the attendance rate of the feverish patients was 73.53%, with the highest rate seen in whose under 10 years old （100%）. Assumed that the sensitivity of paratyphoid fever blood culture was 70%, and the case reporting rate was 90%, we estimated that the annual incidence of paratyphoid fever A in Hongta was 220.33 （95% CI： 170.1-521.4） per 100 thousand, with 965 （95%CI： 745-2284） as new cases. Among all the age groups, the incidence in the age group from 15 to 44 years old was estimated to be at the highest （318.27 per 100 thousand）.Conclusion Hongta seemed to be an endemic region for paratyphoid fever A, with the highest incidence occurred in the age group of between 15 and 44 years old. These findings highlighted the urgent need to carry out further investigation on the risk factors and to implement targeted effective prevention and control measures.