西沙群岛恙螨所携恙虫病东方体的序列分析

目的　用分子生物学技术鉴定西沙群岛恙虫病东方体的基因序列 ,探讨南海岛屿恙虫病疫源地的形成。方法　以巢式聚合酶链反应 (NPCR)检测西沙群岛恙螨所携恙虫病东方体的 5 6kDa蛋白基因片段 ,继而将NPCR产物克隆进pGEM-T载体并且测序 ,测序结果在国际互联网作多序列比较和进化树分析。结果　从西沙群岛收集的恙螨扩增出 5 0 7bp目的片段 ,序列分析证实与Karp株同源性 85 % ,与Gilliam株同源性 6 8% ,与Yonchon株同源性 6 7% ,与Kato株同源性 6 5 %。结论　西沙群岛的恙螨携带恙虫病东方体以Karp型为主。     

新疆博乐地区恙虫病东方体自然疫源地调查报告

目的　调查新疆博乐地区恙虫病东方体（Ot）自然疫源地情况。方法　采用多种方法捕鼠取脾,当地牧民静脉取血、从鼠体表捕获恙螨,用试剂盒提取DNA,应用巢式PCR(nPCR)检测Ot-Sta56基因;阳性标本脾制成悬液,接种昆明小白鼠进行Ot病原进行传代分离。结果　在博乐地区平原湿地、农田和居民区捕鼠126只,其中7只nPCR检测Ot阳性,阳性率5.55%;从当地牧民血液中检测到Ot阳性,阳性率1.87%;从野鼠体表捕获博乐纤恙螨,带螨率为8.4%,检测并分离到Ot病原。DNA序列分析表明,鼠类、人血及恙螨中检测并分离到的Ot碱基序列相同,与Karp株相应DNA片段的碱基序列同源性最高,均为99％,应属于Karp型。在山地草原捕获鼠58只,nPCR检测无Ot阳性,捕获旱獭26只,nPCR检测无Ot阳性,从鼠体表未捕获到恙螨。结论　新疆博乐地区平原湿地可能存在恙虫病东方体自然疫源地,宿主动物可能为小家鼠、普通仓鼠、大沙土鼠,传播媒介可能为博乐纤恙螨     

云南大理地区恙虫病血清学诊断及病原体基因序列分析

目的 对云南大理地区恙虫病做血清学诊断及病原体基因序列分析。方法 采用间接免疫荧光方法(IFA)检测不明原因发热患者血清中的恙虫病东方体(Ot) IgG抗体,用巢式PCR(nPCR)法扩增患者血液中的Ot groEL与sta56基因并对扩增基因做序列分析。结果 19例不明原因发热病例中恙虫病患者8例,其中血清Karp型4例、Kato型3例、Karp和Kato混合型1例;3例确认恙虫病的血样本扩增到groEL基因片段, 其序列同源性为100%,基因序列做系统进化树显示该Ot与Karp和Kato株在同一分支上。从Karp和Kato混合血清型病例血样本扩得sta56基因片断,序列分析显示该Ot与台湾分离株在同一分支上。结论 这些云南大理的恙虫病患者由恙虫病东方体Karp或Kato血清型感染;个别患者可能Karp+Kato混合血清型感染,Karp+Kato混合血清型菌株可能在遗传进化上与某些台湾Ot株关系密切。     

检测恙螨幼虫体内恙虫病东方体DNA用于监测恙虫病流行病学分析

目的　了解恙螨幼虫体内恙虫病东方体自然感染率与恙虫病流行的关系 ,为恙虫病的监测与防治提供理论依据。方法　 1974～ 1982年福建省 49个点捕获的野鼠体表采集恙螨幼虫 910 93只 ,同种为一组用乙醇保存 ,以 10～ 5 0只为一份 ,用东方体 5 6 k Da基因所构进的引物进行 PCR扩增。将结果与 90年代捕获的恙螨幼虫 PCR检测结果比较 ,结合相应年代的恙虫病发病情况进行分析。结果　 1974～ 1981年捕获地里纤恙螨 2 9份、小板纤恙螨 9份 ,高湖纤恙螨 3份、苍白纤恙螨 12份、于氏纤恙螨 1份、中华无前纤恙螨 1份 ,PCR检测恙螨幼虫体内东方体 DNA均为阴性。1982年 12月采集的小板纤恙螨 1份 ,1991年 6 - 7月采集的地里纤恙螨 1份 ,检测到东方体 DNA。结果表明 1982年前恙螨幼虫体内东方体自然感染率极低。结论　恙螨幼虫体内东方体的自然感染率高低与恙虫病流行有密切关系。     

福建近年恙螨感染恙虫病东方体的检测研究

目的　检测恙螨幼虫体内恙虫病东方体, 分析福建恙虫病可能流行的趋势。方法　从福建山区及沿海地区捕鼠采集恙螨幼虫, 通过分类鉴定, 以每只鼠体的寄生螨作为一个被检单位, 用套式 Ｐ Ｃ Ｒ 扩增恙虫病东方体 Ｓｔａ ５８ｋ Ｄａ 基因的８８ｂｐ 片段, 以确定恙螨幼虫是否携带本病原, 继而估计该地区是否存在恙虫病疫源地。结果　从１０５ 份被检单位的恙螨幼虫检出７ 份恙虫病东方体阳性标本, 主要宿主为黄毛鼠, 主要媒介为纤恙螨属的地里纤及小板纤恙螨, 与有关资料比较,证实本省恙虫病的宿主和媒介未发生明显变化。结论　福建沿海地区恙螨的恙虫病东方体的感染率高于山区, 疫源地有继续扩大的趋势。     

安徽省颍上县野鼠体外寄生螨及恙虫病东方体感染调查北大核心CSCD

目的调查颍上县野鼠的种类、体外寄生恙螨的种类以及恙虫病东方体的感染情况。方法于2019年9~11月在阜阳市颍上县的十八里铺镇、半岗镇、耿棚镇等地采用笼日法捕获野鼠,采集野鼠体表的恙螨,并对野鼠和恙螨的种类进行鉴定,计算带恙螨率和带恙螨指数;无菌操作解剖野鼠,并采集野鼠的脾脏,低温保存,分别提取脾脏和恙螨的总DNA,采用巢氏PCR扩增恙虫病东方体56 kD表面蛋白基因。结果共捕鼠50只,其中黑线姬鼠有45只,为当地野外的优势鼠种。共采获寄生螨虫776只,隶属于4科5属7种,其中恙螨的数目最多,共759只,带恙螨的野鼠有33只,总带恙螨率是66.00%,带恙螨指数是15.18。恙螨占97.81%,属于1科1属3种;其次是革螨,17只,占2.19%,属3科4属4种。小盾纤恙螨是当地恙螨的优势种(597只,占78.66%),其次是高湖纤恙螨(107只,15.16%),须纤恙螨最少(55只,7.79%);革螨包括毒厉螨(7只),耶厉螨(6只),囊螨(1只)和鞍形赫刺螨(3只)。对50只野鼠的脾脏标本进行恙虫病东方体PCR检测,均为阴性。30份恙螨标本中有1份恙虫病东方体PCR检测为阳性,阳性率为3.34%。结论颍上县野鼠带恙螨率和带恙螨指数比较高,恙螨中发现自然感染恙虫病东方体,应开展人群流行病学调查。     

福建近年恙螨感恙虫病东方体的检测研究

目的 检测恙螨幼虫体内恙虫病东方体,分析福建恙虫病可能流行的趋势。方法 从福建山区及沿海地区捕鼠采集恙螨幼虫,通过分类鉴定,以每只 本的寄生螨作为一个被检单位,用套式ＰＣＲ扩增恙虫病东方体ｓｔａ ５８ｋＤａ基因的８８ｂｐ片段,以一恙螨幼虫是否携带同原,继而估计该地区是否存在恙虫病疫源地。结果 从１０５份被检单位的恙螨幼虫检发恙虫病东方体阳性标本,主要宿主为黄毛鼠,主要媒介为纤恙螨属的地里纤及及小板     

南澎列岛恙虫病东方体分离株的基因分型

目的 用分子生物学技术鉴定南澎裂岛恙虫病东方体及其分型。方法 以巢式聚合酶链反应（NPCR）检测南澎列岛恙虫病东方体8个分离株的56kD蛋白基因片段,阳性产物进行限制性片段长度多态性分析（RFLP）。选择其中4株的PCR产物克隆进pGEM－T载体并且测序,测序结果在国际互联网作多序列比较和进化树分析。结果 7株分离株扩增出500bp目的片段,RFLP分析表明南澎列岛存在三种不同的恙虫病东方体。从4个样品获得7个克隆,序列分析证实2个克隆（DY1,DY21）与Yonchon同源性99％,3个克隆（DY22,NY12,NS2）与Karp株同源性92％,2个克隆（NY11,NS1）与Kato株同源性98％。南澎列岛存在Karp,Kato,Yonchon三种类型的恙虫病东方体。     

应用PCR／RFLP对辽宁、吉林地区恙虫病东方体分离株的基因型分析

目的 鉴定辽宁、吉林地区恙虫病东方体分离株的基因型。方法 采用ＰＣＲ／ＲＦＬＰ技术对辽宁、吉林地区恙虫病东方体分离株的ｓｔａ５６目的基因进行分析研究,并与国际参考株进行比较。结果 辽宁、吉林地区６株分离株的ＰＣＲ特异性产物经Ｈｉｎｆ Ⅰ、ＨｈａⅠ、ＲｓａⅠ酶切后呈现２种不同的ＲＦＬＰ图谱：ＨＣＡａ９２０２株、ＨＣＡｐ９２０３株及ＨＣＭ９５０１株与Ｇｉｌｌｉａｍ参考株具有相似的酶切图谱,但缺乏Ｈｉｎ     

检测恙螨幼虫体内恙虫病东方体DNA用于监测恙虫病流？…

目的 了解恙螨幼虫体内恙虫病东方体自然感染率与恙虫病流行的关系,为恙虫病的监测与防治提供理论依据。方法 １９７４～１９８２年福建省４７个点捕获的野鼠体表采集恙螨幼虫９１０９３只,同种为一组用乙醇保存,以１０～５０只为一份,用东方体５６ｋＤａ基因所构进的引物进行ＰＣＲ扩增。将结果与９０年代捕获的恙螨幼虫ＰＣＲ检测结果比较,结合相应年代的恙虫病发病情况进行分析。结果 １９７４～１９８１年捕获地里纤恙螨     

Characterization of Orientia tsutsugamushi strains isolated in Shandong Province, China by immunofluorescence and restriction fragment length polymorphism (RFLP) analyses

In order to identify the characteristics of the Sta56 gene of the 23 isolates of Orientia (O.) tsutsugamushi isolated in Shandong Province, indirect immunofluorescence assay (IFA) was used to identify the gene type of 23 strains O. tsutsugamushi isolated from scrub typhus patients, chigger mites, and rodents. Restriction fragment length polymorphism (RFLP) analysis was also used to analyze the restriction profiles of the Sta56 gene PCR amplification products of the 23 isolated strains of the O. tsutsugamushi; the results were compared with those acquired by nested PCR. By IFA, 21 of the 23 isolates belonged to the Gilliam type, and 2 to the Karp type. Using RFLP analysis, 21 strains had similar restriction profiles to the Japan Kawasaki strain, but they had no restriction site Hha I, and thus had some difference in gene sequence compared with the Japan Kawasaki strain. The other 2 strains had similar restriction profiles to Karp. These results were identical to that acquired by nested-PCR. In Shandong Province, the gene types of epidemic O. tsutsugamushi strains were similar to the Japan Kawasaki type, but had some differences in gene sequence. In addition, Karp also existed.     

南澎列岛恙虫病立克次体分离株的PCR/RFLP分析

目的　利用ＰＣＲ／ＲＦＬＰ方法证实南澎列岛是恙虫病的疫源地并对恙虫病立克次体初步分型。方法　采用套式聚合酶链反应（ＮＰＣＲ）扩增恙虫病立克次体５６ｋＤ蛋白基因片段,阳性标本的扩增产物进行限制性片段长度多态性（ＲＦＬＰ）分型。结果　南澎列岛的８ 株恙螨／野鼠分离株中７ 株与南澳岛的１ 株扩增出阳性带;ＲＦＬＰ图谱分析表明南澎列岛存在三个型别的立克次体感染,其中一型酶切图谱与Ｋａｒｐ 株相同,一型图谱与Ｋａｔｏ 相同,还有一型既不同于Ｋａｒｐ,也不同于Ｋａｔｏ、Ｇｉｌｌｉａｍ 。并且７株当中有５株为混合感染。南澳岛分离株酶切图谱与Ｋａｒｐ 株相同。结论　本文结果证实了南澎列岛和南澳岛是恙虫病疫源地。南澎列岛上存在三个型别的立克次体,不同型别的立克次体可形成双重感染     

恙虫病的预防与控制

恙虫病主要流行于我国南方，主要动物宿主为啮齿类，媒介为恙螨。我国恙虫病按季节分布可分为两型：（1）夏季型，流行于南方；主要动物宿主为黄毛鼠、黄胸鼠；主要媒介为地里纤恙螨；流行于5-10月；恙虫病东方体型别为Gilliam。（2）秋冬型，流行于江苏、山东省；主要动物宿主为黑线姬鼠、褐家鼠、大仓鼠；主要媒介为小盾纤恙螨；流行于10-12月；恙虫病东方体型别为Kawasaki。以环境治理、灭螨、灭鼠和做好个体防护作为防控方法。     

Epidemiological studies on host animals of scrub typhus of the autumn-winter type in Shandong Province, China

In order to elucidate the host animals of scrub typhus in Shandong Province, epidemiological studies on host rodents of the autumn-winter type scrub typhus were carried out from 1995 to 2002 at four localities in the Shandong Province. Based upon ecological observations of the composition, seasonal fluctuation of animal hosts, isolation of Orientia tsutsugamushi, detection and identification of serotypes of antibodies to O. tsutsugamushi were conducted. Two thousand eight hundred and eighty-four rodents and insectivores were captured, including 2,055 Apodemus agrarius (71.26%), 408 Cricetulus triton (14.15%), 64 C. barabensis (2.22%), 12 Crocidura suaveolens (0.42%), 313 Rattus (R.) norvegicus (10.85%), 32 Mus (M.) musculus (1.11%). A. agrarius was predominant in the field and the seasonal fluctuation was correlated significantly to that of scrub typhus (r=0.810, p<0.005). R. norvegicus was predominant indoors. The average capture rate per year in the field was 12.76% from 1995 to 1997. Of the total 2,884 rodents and insectivores captured out- and in-doors, 527 were living rodents (including 335 A. agrarius, 119 C. triton, 6 C. barabensis, 2 C. suaveolens, 63 R. norvegicus and 2 M. musculus, and 15,467 chigger mites were collected from them. Two hundred and fifty-three of 335 A. agrarius were parasitized by chiggers, showing 75.52% (253/335) of the infestation rate and 17.53 of the chigger index; 106 C. triton were parasitized by chiggers, showing 89.08% (106/119) infestation rate and 75.93 of the chigger index. The average antibody positive rate of rodents was 14.78%. The seasonal change of the antibody positive rate was higher during December-February (the second year), and varied from 20% to 28%, but the level of antibodies remained relatively low (5.26-16.67%) during March-November. The results of serotyping with 47 antibody-positive sera were as followings: 39 sera were Gilliam types, 7 sera were Karp types, 1 serum was Kato type. Twelve strains of O. tsutsugamushi were isolated from A. agrarius (8 strains), C. triton (3 strains) and R. norvegicus (1 strain), out of the isolated 12 strains, 10 were Gilliam strains, 2 were Karp strains. A. agrarius and R. norvegicus were the main host animals in out- and indoors respectively.     

用PCR检测现场单个小盾纤恙螨体内恙虫病立克次体的研究

恙虫病立克次体表面蛋白５６ＫＤａ基因编码区构建的群特异引物，采用嵌合式聚合酶链反应检测现场捕获的单个小盾纤恙螨幼虫体内Ｒ．ｔ的ＤＮＡ。共检测江苏省恙虫病疫区小盾纤恙螨幼虫６１只，结果２只幼虫提取的ＤＮＡ经扩增后见４８１￣５０７ｂｐ的ＤＮＡ扩增带，表明这２只幼虫携带有Ｒ．ｔ，其该种螨Ｒ．ｔ携带率为３．２７％，证明该法可用于单个恙螨幼虫体的Ｒ．ｔ的检测，对恙虫病疫区媒介恙螨的流行病学调查具有实用价值。     

云南省永善县恙虫病流行病学调查

目的 对云南省永善县恙虫病开展流行病学调查。方法 应用胶体金免疫试验对发热患者血清进行恙虫病东方体(Orientia tsutsugamsushi)IgG和IgM抗体检测,采用夜夹法诱捕调查地区鼠类,用巢氏PCR方法对鼠脾脏做groEL基因片段扩增和基因序列分析。结果 2015年5-10月在永善县发现恙虫病患者34例,其中实验室确诊病例21例,临床诊断病例13例;主要发病于8月,占总病例数的32.35%;40—49岁年龄组发病最多,占总病例数的32.35%;农民发病数最多,占总病例数的79.41%;有焦痂或溃疡的病例占总病例数的94.12%,其中位于腹股沟最多(占有焦痂或溃疡患者的31.25%);有皮疹的病例占总病例数的50.00%。在捕获的39份黄胸鼠(Rattus flavipectus)脾组织样品中,恙虫病东方体groEL基因片段扩增阳性9份(阳性率23.08%)。groEL基因片段序列进化树分析显示本次检测到的YSP30株与的HSB1、FAR1、UAP4等Saitama型菌株的遗传进化关系最密切, 检测到的其余8株与UT213、UT221、SH205等Karp型菌株的遗传进化关系最密切。结论 血清学和分子生物学方法证实了永善县存在恙虫病疫源地,当地存在Karp和Saitama相关的2种基因型恙虫病东方体。     

安徽三界地区啮齿动物感染恙虫病东方体调查

目的调查安徽三界地区啮齿动物自然感染恙虫病东方体分离株,并确定其基因型别。方法流行季节在野外用鼠笼捕鼠并鉴定鼠种、携螨率;巢式PCR对鼠脏器进行恙虫病东方体56kD基因片段检测;将鼠脏器接种小自鼠进行病原体分离,PCR扩增分离株0t56kD基因片段,并将目的片段进行测序,基因序列同源性及进化分析。结果捕获啮齿动物数及其携螨率,黑线姬鼠60％（15／25）;褐家鼠45．5％（5／11）;东方田鼠和购睛各2只,均阴性。40只野鼠脏器有3只恙虫病东方体PCR扩增阳性,阳性率为7．5％;从黑线姬鼠标本中分离到1株恙虫病东方体Sanjie,56kD基因片段测定该株与台湾TT071la和NT0511b分离株同源性最高（98％）,系统发生树分析也显示与Kawasaki型共处于同一分支。结论安徽三界地区存在鼠类恙虫病东方体自然感染,黑线姬鼠为其主要宿主,当地恙虫病东方体属Kawasaki基因型。     

恙虫病东方体目视LAMP现场化检测方法的建立

目的 建立基于"染料-蜡丸"的目视LAMP检测恙螨中恙虫病东方体的方法,为恙虫病的防治提供新工具.方法 选择Ot GroEL基因作为检测靶序列,在线设计并合成LAMP引物.构建rOt-GroEL重组质粒作为阳性对照.建立基于SYBR Green I的"染料-蜡丸"目视LAMP,并联合便携式LAMP仪使其利于现场应用.结...     

Detection of Orientia tsutsugamushi, the causative agent of scrub typhus, in a novel mite species, Eushoengastia koreaensis, in Korea

To identify potential vector species of scrub typhus in the Republic of Korea (ROK), chigger mites were harvested from wild rodents captured at nine localities in October 2005. The bodies of the chigger mites were individually punctured with a fine pin, squeezed out internal contents, and examined for Orientia tsutsugamushi DNA by nested polymerase chain reaction. The exoskeleton of associated chiggers was mounted on glass slides with polyvinylalcohol (PVA) medium for identification. Among 830 individuals belonging to 4 genera and 14 species, O. tsutsugamushi was detected from 22 chiggers of six species, with an overall infection rate of 2.7%. The infection rate was highest for Leptotrombidium palpale (5.3%), followed by Neotrombicula japonica (4.3%), Leptotrombidium scutellare (3.7%), Leptotrombidium orientale (3.6%), Eushoengastia koreaensis (1.9%), and Leptotrombidium pallidum (1.5%). This study first reported O. tsutsugamushi infection from N. japonica and E. koreaensis larvae in the ROK. The population densities of L. pallidum (33.4 chiggers/rodent), historically confirmed as a primary vector of scrub typhus in the ROK, were high, whereas its infection rate was relatively low (1.5%). However, E. koreaensis was only collected from 154 individuals at seven collection sites and its infection rate was demonstrated relatively high (mean 1.9%). Additional studies are needed to determine the role of vector species in the epidemiology of scrub typhus.