陕西省莱姆病自然疫源地调查研究

Investigation of Lyme disease natural epidemic focus in Shaanxi Province

目的调查了解陕西省莱姆病自然疫源地。方法人群莱姆病螺旋体血清抗体检查,采用间接免疫荧光法(IFA);莱姆病患者,采用个案调查;蜱样,采用拖旗法采集;莱姆病螺旋体检测,采用巢式PCR法;莱姆病螺旋体基因分型,采用RFLP法。结果通过血清流行病学调查,陕西省富县张家湾镇、南郑县碑坝、陇县八渡镇3个农林地区人群莱姆病螺旋体自然感染率分别为8.33%(6/113)、8.88%(3/36)和7.51%(4/45)(P>0.05),发现莱姆病患者14例,蜱类以嗜群血蜱和达吉克斯坦革蜱为优势种,检测蜱样1 116只。检测出阳性138只,总阳性率为12.35%。物种的阳性率分别为嗜群血蜱30.06%(107/356),达吉克斯坦革蜱3.88%(29/747),日本血蜱15.38%(2/13);检测出阳性蜱样138只,其中嗜群血蜱107只,84只为伽氏疏螺旋体基因型,23只为阿弗西尼疏螺旋体基因型;达吉克斯坦革蜱29只,24只为伽氏疏螺旋体基因型,5只为阿弗西尼疏螺旋体基因型;日本血蜱2只,均为伽氏疏螺旋体基因型。结论研究提示陕西省富县张家湾镇、南郑县碑坝、陇县八渡镇3个农林地区存在莱姆病自然疫源地。

Objective To investigate natural epidemic focus of Lyme disease in Shaanxi Province.Methods The sera antibody of Lyme disease people were examined by indirect immunofluorescent assay（IFA）;Lyme disease patients were found by case survey method;tick samples were collected by drag flag method;Borrelia burgdorferi from tick samples were detected by nest PCR method;Borrelia burgdorferi genotype were analyzed by RFLP method.Results Lyme disease Borrelia burgdorferi natural infection rate were 8.33 %（6/113）,8.88%（3/36）and 7.51%（4/45）（P0.05）respectively in Fu county Zhang Jia Wan town,NanZheng county BeiBa and Long county BaDu town in Shaanxi Province.14 of Lyme disease patients were found.H.concinna and D.daghestanicus were dominant species in Shaanxi Province.1 116 of the tick samples were detected,138 of which were positive,the positive rate was 12.35%.The positive rate of H.concinna was 30.06%（107/356）,D.daghestanicus was 3.88%（29/747）,H.japonica was 15.38%（2/13）.107 of 138 positive tick samples were H.concinna,84 were B.garinii genotype,23 were B.afzelii genotype;29 of 138 were D.daghestanicus,24 were B.garinii genotype,5 were B.afzelii genotype;2 H.japonica were B.garinii genotype.Conclusion Based on this survey,there are new Lyme disease natural epidemic focus existing in three forest areas,Fu county Zhang Jia Wan town,NanZheng county BeiBa and Long county BaDu town in Shaanxi Province.