山东省秋冬型恙虫病自然疫源地调查

Investigation on natural foci of autumn-winter type tsutsugamushi disease in Shandong province

目的 摸清驻地恙虫病的本底资料 ,指导军民做好本病防治工作。方法 采用病原学、血清学技术和流行病学调查方法 ,对山东地区进行秋冬型恙虫病自然疫源地调查。结果 结果表明山东地区恙虫病流行高峰为 10月份 ,约占发病数的 80 % ,属秋冬型 ;以黑线姬鼠、褐家鼠、大仓鼠为主要储存宿主 ,分别占 82 .87%、85 .47%和 13.0 4% ;当地小盾纤恙螨、须纤恙螨、临淮岗纤恙螨、太平洋无前恙螨均存在自然感染或分离到恙虫病立克次体 (Rt) ,证实以小盾纤恙螨为主要传播媒介 ;从恙虫病患者血液 ,鼠类和恙螨等分离到Rt 41株 ,属弱毒株 ;血清型以Gilliam型为主 ,占 90 % ;病例呈散发分布 ,有聚集性 ,患者 80 %以上为青壮年农民 ;临床表现为轻型 ,不同地区有差异。

Objective In order to provide basic data of tsutsugamushi disease in Shandong province, for the control and prevention of this disease in residents and armymen. Methods Aetiological, serological and epidemiological methods were used to investigate the natural foci of autumnwinter type tsutsugamushi disease. Results The peak of tsutsugamushi disease epidemic in Shandong province was in October with cases in this month accounted for 80% of all in a year, that showed autumnwinter type. The main reservoir hosts were Apodemus agrarius,Rattus norvegicus and Cricetulus triton, accounted for 82.87 %, 85.47 % and 13.04 % respectively. It was confirmed that natural infection existed among Leptotrombidium(L.) scutellare, L.palpalis, L.linhuaikonense and Walchia pacifica. The main vector of transmission was Leptotrombidium scutellare. 41 strains of Rickettsia tsutsugamushi were isolated from the blood samples of patients, rodents and chigger mites but with weak toxicity. 90% of the serotypes of the strains belonged to Gilliam type. The distribution of the cases had a sporadic nature. More than 80% of the cases were young or middle aged peasants. Clinical symptoms were mild, with some differences in different areas. Conclusion The natural foci type of tsutsugamushi disease in Shandong could be divided into plain and hilly types.