安徽省恙虫病新疫源地疫情暴发特点及意义

Features and significance of tsutsugamushi disease outbreaks in the emerging epidemic focuses in Anhui Province

目的调查安徽省恙虫病新疫源地多起疫情暴发的流行病学和临床特点,阐明我国恙虫病疫源地分布的相应新变化。方法采用现场流行病学调查、病史及检验结果分析、文献复习等方法,系统分析安徽省历次恙虫病疫情暴发的时间、地点、规模、地理、气候、虫媒、病原学、易感人群、临床特点及诊治情况。结果 2007年以来安徽省多次出现恙虫病疫情暴发。2007年秋季滁州地区偏潮湿丘陵丛林地带发现19例,其中18例经胶体金免疫色谱法确诊。2008年秋季阜阳、亳州、蚌埠等偏干燥平原地区分别报告156、9、70例,恙虫病东方体为Kawasaki基因型。2009和2010年秋季阜阳等地相继有疫情暴发。患者多有恙虫病典型临床表现,给予盐酸多西环素或阿奇霉素抗感染治疗后均迅速痊愈。结论安徽省存在广泛的恙虫病新疫源地,为一般流行区。滁州地区恙虫病为过渡型疫源地丘陵型秋冬型,阜阳等地为过渡型疫源地平原型秋冬型。盐酸多西环素或阿奇霉素治疗恙虫病有特效。

Objective To investigate the epidemiological and clinical features of tsutsugamushi disease outbreaks in the emerging epidemic focuses in Anhui Province, and to clarify the new changes in the geographical distribution of tsutsugamushi disease in China. Methods The time and seasons, sites, scales, geographical distribution, climate, insect vectors, pathogens, susceptible popu- lations, clinical features, diagnosis and treatment of tsutsugamushi disease outbreaks in Anhui Province were systematically analyzed by way of on-the-spot epidemiological investigation and review of the case history, laboratory findings and published literatures. Results Outbreaks of tsutsugamushi disease have been validated in Anhui Province since 2007. Nineteen cases were found in the damp foothill zones in Chuzhou in the autumn of 2007, and 18 of them were confirmed by colloidal gold immunochromatographic as- say. At least 156, 9 and 70 cases were reported in the outbreaks in Fuyang, Bozhou, and Bengbu （plain regions with dry weather） in the autumn of 2008, respectively, and the pathogen was identified as Kawasaki genotype of Orientia tsutsugamushi. Another out- breaks of tsutsugamushi disease were validated in Fuyang and other cities in Anhui Province in the autumn of 2009 and 2010. Most of the patients had typical clinical manifestations of tsutsugamushi disease. All the patients were cured after the administration of doxycycline or azithromycin. Conclusions Epidemic focuses of tsutsugamushi disease are newly found in Anhui Province. Chuzhou and Fuyang are transitional epidemic focuses where the outbreaks of tsutsugamushi disease occur in foothill zones and plain regions, respectively, in autumn and winter. Doxycycline or azithromycin is the effective agent for Orientia tsutsugamushi.