吉林省长白山区斑点热立克次体自然疫源地调查

目的　了解吉林省长白山区蜱传斑点热的自然疫源地情况。方法　利用立氏立克次体[相对分子质量 (Mr) 190× 10 3 ]外膜蛋白A(R .rOmpA)基因序列设计引物 ,对 6 83只蜱类标本进行聚合酶链反应 (PCR)检测 ,并随机抽取一株森林革蜱阳性扩增产物进行克隆与序列测定。结果　从森林革蜱和嗜群血蜱标本中检测出了斑点热立克次体DNA片段 ,阳性率分别为 5 3.81%和 7.4 1% ;所测序列与前苏联的DnS 14株的同源性为 10 0 .0 0 % ,与DnS 2 8和RpA 4的同源性均为99.0 0 % ;而与国内所检测的BJ 90、HLJ 0 5 4的同源性分别为 88.0 0 %和 86 .0 0 %。结论　长白山区存在斑点热的自然疫源地 ,存在与DnS 14株型别一致的斑点热立克次体 ,在中国系首次发现。     

广东省大埔县斑点热群立克次体血清学调查

目的：调查大埔县健康人群及鼠、牛中斑点热群立克次体分布情况。方法：微量室温补体结合法。结果：在２８２名健康人群血清中，２９例西伯利亚立克次体抗体阳性，阳性率为１０２８％（２９／２８２）；１１例康氏立克次体抗体阳性，阳性率为３９０％（１１／２８２）；１６例小蛛立克次体阳性，阳性率为５６７％（１６／２８２）。３０份鼠血清，西伯利亚立克次体抗体阳性率为１３３３％（４／３０），康氏立克次体抗体阳性率为３３３％（１／３０），小蛛立克次体抗体阳性率为１０００％（３／３０）。２５份牛血清，西伯利亚立克次体抗体阳性率为８００％（２／２５），康氏立克次体抗体阳性率为４００％（１／２５），小蛛立克次体抗体阳性率为４００％（１／２５）。结论：广东省大埔县林区存在有斑点热的自然疫源地。     

广东省首次分离斑点热群立克次体

目的 从宿主动物及蜱中分离斑点热群立克次体，以了解广东省是否存在斑点热自然疫源地。方法 从广东省封开县七星自然保护区采用笼日法捕活鼠，采集鼠脾及鼠表的蜱，用PCR进行初筛，鸡胚卵黄囊培养法直接分离立克次体，血清学试验对分离株进行鉴定。结果 采集鼠脾103份，鼠表的蜱38匹；从2只针毛鼠体表捉获的蜱中分离到2株斑点热群立克次体，命名为GDFK58—2000株、GDFK59—2000株立克次体，经血清学鉴定为西伯利亚种。结论 首次从病原学上证实了广东省存在斑点热自然疫源地。     

福建省宁化县斑点热群立克次体的研究

「目的」对已知的宁化县斑点热群立克次体疫源地进行全面系统ＳＦＧＲ感染情况调研。「方法」采用微量室温补体结合法（ｍＣＦ）和间接免疫荧光（ＩＦＡ）法;鸡胚卵巢黄囊感染法并用ｍＣＦ、ＰＣＲ／ＲＦＬＰ分子生物学技术进行鉴定。「结果」人群血清阳性率为１２．７％（１２１／９５２）。宿主动物ＳＦＧＥ感染,抗体阳性率０～５５．６％不等。鉴定分类各种蜱５６００余只,共６属１３种。从野兔、麂体表寄生的越原血蜱中分离出     

部分地区蜱传斑点热自然疫源地调查

198 4年 ,我们在自然疫源性疾病的调查中从黑龙江省东宁县蜱类分离到多株立克次体 ,经免疫学与分子生物学鉴定确认为斑点热群 (Spottedfevergroup ,SFG)立克次体新种 ,命名为黑龙江立克次体〔1～ 5〕。为此 ,多年来我们对黑龙江省和吉林省东部的东宁县与珲春县进行了蜱传斑点热的自然疫源地调查。现将结果报告如下。1　对象与方法1 1　对象　依据地势、地貌、植被 ,选择不同生境点作为调查点进行流行病学调查与疑似病人调查。1 3　方法　 (1)标本采集 :捕获野鼠 ,采用日笼法 ,每半月布笼 1次 ,每次每种生境 30 0鼠笼 ,捕获野鼠 ,分类鉴定…     

某部驻区蜱传斑点热自然疫源地调查

目的了解某部驻区蜱传斑点热的自然疫源地情况。方法进行蜱类与啮齿动物调查，利用立氏立克次体190kD外膜蛋白A(R．rOmpA)基因序列设计引物，对683只蜱类标本和146个鼠类脏器标本进行PCR检测，随机抽取一株森林革蜱阳性扩增产物进行序列测定。结果调查地区存在3种蜱、5种啮齿动物；从森林革蜱、嗜群血蜱和啮齿动物脏器标本中检测斑点热立克次体DNA片段，阳性率分别为53．81％、7．41％和6．16％；所测序列与前苏联的DaS 14株的同源性为100％，与我国检测的BJ-90、HLJ-054的同源性分别为88％和86％。结论调查地区存在与DaS14株型别一致的斑点热立克次体株。     

斑点热群立克次体广东分离株OmpA基因片段的克隆及序列分析

目的 鉴定斑点热群立克次体广东分离株GDFK58－2000和GDFK59－2000种属类型。方法 用PCR方法扩增GDFK58－2000和GDFK59－2000的OmpA基因起始部位533bp片段，克隆于pMD18-T载体并进行测序，测序结果与Genbank中其它斑点热群立克次体相应基因片段的核苷酸进行比较，用DNASTAR软件分析结果。结果 GDFK58－2000、GDFK59-2000和西伯利亚立克次体之间的核苷酸同源性为99.6%-99.8%，推断的氨基酸同源性为99.6%-99.8%，常用于分类鉴定的酶切位点完全一致。结论 两株广东分离株属于斑点热群立克次体的西伯利亚立克次体种。     

福建省宁化县斑点热疫源地的调查研究

斑点热 (ｓｐｏｔｔｅｄｆｅｖｅｒ,ＳＦ)是由一组斑点热群立克次体(ｓｐｏｔｔｅｄｆｅｖｅｒｇｒｏｕｐｒｉｃｋｅｔｔｓｉａ ,ＳＦＧＲ)引起的一种人兽共患蜱媒自然疫源性疾病。其主要通过森林中蜱、螨的吸血活动在人和动物间传播。福建省宁化林区斑点热的存在已被我们以往工作所证实[1,2 ] 。为进一步查明福建省宁化林区斑点热群立克次体在人群及宿主动物、媒介蜱类中感染情况及疫源地类型 ,1993年至今我们采用现场调查、血清学检测、病原分离和分子生物学技术等进行研究。现将结果报告如下一、材料与方法1.材料来源 :(1)血清样本 :人血…     

滇西鼠疫疫源地野外鼠形动物斑点热群立克次体和莫氏立克次体感染调查

目的了解滇西鼠疫疫源地野外鼠形动物斑点热群立克次体(spotted fever groupRickettsiae, SFGR)和莫氏立克次体(Rickettsia mooseri, R.mooseri)感染情况。方法应用磁珠法提取2015-2016年自滇西梁河县、剑川县和玉龙县鼠疫疫源地捕获的2 512只野外鼠形动物肝脏样本DNA, 选用热休克蛋白groEL基因引物进行巢式PCR扩增。分别采用DNAStar 7.1软件和美国国家生物技术信息中心(NCBI)的GenBank进行基因序列剪切、拼接和Blast同源性比对分析, 同时采用DNAStar 7.1软件和MEGA 6.0软件构建系统发育树。结果感染SFGR的野外鼠形动物有锡金小鼠、斯氏家鼠、灰麝鼩和臭鼩鼱(各1只), 总感染率为0.16%(4/2 512);未检出R.mooseri感染。梁河县和剑川县鼠疫疫源地野外鼠形动物SFGR感染率分别为0.49%(3/611)和0.10%(1/1 029), 玉龙县鼠疫疫源地野外鼠形动物未检出SFGR感染。同源性分析显示, SFGR阳性样本的基因序列与参考序列同源性为95.45%～100.00...     

海南岛斑点热疫源地的调查研究

本文报告在海南岛发现了斑点热疫源地，其人群北亚斑点热抗体的阳性率３８．３％，鼠类抗体阳性率５３．０％。从７种鼠检出抗体，其中优势种黄毛鼠（Ｒａｔｔｕｓｌｏｓｅａ）、黄胸鼠（Ｒ．ｆｌａｖｉｐｅｃｔｕｓ）和海南屋顶鼠（Ｒ．ｒａｔｔｕｓｈａｉｎａｎｉｃｕｓ）阳性率＞５０．０％，应用ＰＣＲ技术从该３种鼠检出斑点热群立克次体特异ＤＮＡ。小兽类寄生蜱３种、革螨５种，优势种分别为粒形硬蜱（Ｉｘｏｄｅｓｇｒａｎｕｌａｔｕｓ）和毒棘厉螨（Ｌａｅｌａｐｓｅｃｈｉｄｎｉｎｕｓ）；牛羊寄生蜱为微小牛蜱（Ｂｏｏｐｈｉｌｕｓｍｉｃｒｏｐｌｕｓ）。从粒形硬蜱和微小牛蜱检出斑点热群立克次体特异ＤＮＡ。     

河北省西部山区蜱传斑点热群立克次体分子流行病学研究

目的 调查河北省西部山区蜱类斑点热群立克次体带菌情况,为蜱传斑点热群防控提供科学依据.方法 根据已发表斑点热群立克次体OmpA外膜蛋白基因序列设计特异性引物,对河北省西部山区采集的长角血蜱进行PCR检测,并对阳性样本进行测序和序列分析,建立分子系统进化树.结果 在1227份蜱DNA样本中检测出91份阳性,阳性率为7.42％;序列分析结果显示河北省西部山区长角血蜱携带立克次体与河北株暂定种(登录号:HQ651815、HQ651817、HQ651818、HQ651819、HQ651823、HQ651824)、福建株FUJ(登录号:AF169629)同处于一个分支,与河北株立克次体暂定种同源性最高(99.02％),其次是福建株(98.50％)、黑龙江立克次体绥芬株HLJ-054(登录号:AF179362)和黑龙江立克次体虎林株HL-93(登录号:AF179364)(98.13％)、日本株YM(登录号:U43795)(97.92％).结论 河北省西部山区蜱传斑点热群立克次体感染较为严重,应尽快制定防制措施,以免危及动物及人类健康.     

The guinea pig model for tick-borne spotted fever rickettsioses: A second look

The guinea pig (Cavia porcellus) has an established track record as an animal model, with its utility in rickettsial research documented as early as the turn of the 20^th century. From identifying Rickettsia rickettsii as the agent of Rocky Mountain spotted fever and ticks as the natural transmission route to evaluating protective immunity and treatment for tick-borne rickettsiae, guinea pigs have been essential for advances in our understanding of spotted fever rickettsioses (SFR). Tick feeding on guinea pigs is feasible and results in transmission of tick-borne rickettsiae. The resulting infection leads to the recapitulation of SFR as defined by clinical signs that include fever, unthrift, and in the case of transmission by a Rickettsia parkeri-infected Amblyomma maculatum tick, a characteristic eschar at the site of the bite. No other small animal model recapitulates SFR, is large enough to collect multiple blood and skin samples for longitudinal studies, and has an immune system as similar to the human immune system. In the 1980s, the use of the guinea pig was significantly reduced due to advances made to the more reproductively prolific and inexpensive murine model. These advances included the development of genetically modified murine strains, which resulted in the expansion of murine-specific reagents and assays. Still, the advantages of the guinea pig as a model for SFR persist, novel assays are being developed to better monitor guinea pig immune responses, and tools, like CRISPR/Cas9, are now available. These technical advances allow guinea pigs to again contribute to our understanding of SFR. Importantly, returning to the guinea pig model with enhanced tools will enable rickettsial researchers to corroborate and potentially refine results acquired using mice. This minireview summarizes Cavia porcellus as an animal model for human tick-borne rickettsial diseases.     

吉林省珲春地区蜱中伯氏疏螺旋体与斑点热群立克次体复合感染研究

目的了解吉林省珲春地区伯氏疏螺旋体与斑点热群立克次体的复合感染情况.方法运用PCR方法对吉林省珲春地区采集的蜱标本,进行伯氏疏螺旋体5S～23S rRNA间隔区基因与斑点热群立克次体外膜蛋白A（ompA）基因的检测.测序并用PHYLIP软件进行序列分析.结果全沟硬蜱中伯氏疏螺旋体感染率为36.0%,在全沟硬蜱中检测到了斑点热群立克次体的感染,其感染率为2 0%.二者的复合感染率为2.0%;森林革蜱中伯氏疏螺旋体感染率30.9%,斑点热群立克次体感染率29.1%,二者的复合感染率16.8%.伯氏疏螺旋体的序列分析显示吉林地区的伯氏疏螺旋体都属于B.garinii基因型,同源性较高.对斑点热阳性片段序列分析表明新测序列与斯洛伐克新发现的IRS3株和IRS4株核苷酸序列同源性为97%.结论吉林省珲春地区全沟硬蜱及森林革蜱中检测到伯氏疏螺旋体与斑点热群立克次体的感染,并检测到2种病原体的复合感染情况.     

浙江省蜱标本中斑点热群立克次体rOmpA和gltA基因检测

目的了解浙江省部分山区蜱中感染斑点热群立克次体的状况,探讨以外膜蛋白A（rOmpA）和柠檬酸合成酶基因（gltA）为靶基因的PCR方法可行性。方法利用PCR方法,检测天台县左溪镇和临安县西天目地区共46组蜱类标本中rOmpA和gltA基因特异片段。对所检测到的阳性结果进行克隆与序列测定,并进行聚类分析。结果从46组蜱标本中检测发现2组长角血蜱中斑点热群立克次体的rOmpA和gltA基因片段均为阳性,核酸序列基本一致,但推测斑点热群立克次体种的进化位置存在差异。结论浙江省部分山区存在蜱中感染斑点热群立克次体的状况。利用rOmpA和gltA基因能从标本中检测到斑点热群立克次体,但从2个结果推测立克次体的分类位置存在差异。     

Prevalence of antibodies to spotted fever group rickettsiae in human beings and dogs from an endemic area of mediterranean spotted fever in Catalonia, Spain

We assessed the prevalence of antibodies to spotted fever group rickettsiae in human beings and dogs by indirect immunofluorescence in the region of 'Vallés Occidental', Barcelona (Spain). In the group of 150 serum samples from patients without former history of Mediterranean spotted fever, 12 had antibodies to Rickettsia conori. The overall seroprevalence was 8% (95% confidence interval, 4.6% to 13.5%). There were no statistically significant differences between the mean ages of patients with positive and negative antibodies to R. conorii. However, seropositivity was significantly more common among patients living in semi-rural areas. In the group of 138 dog serum samples, 36 (26.1%) sera had antibodies to R. conorii. When the present results were compared with those obtained in a previous seroepidemiological survey carried out in the same geographical region in 1987, no significant differences were found. Therefore, although the epidemiological markers have dropped, this does not absolutely confirm the decrease of the presence of R. conorii in this area.     

斑点热群立克次体HN-98株的分离和初步鉴定

目的 从海南省斑点热疫源地不明热病人体内分离斑点热群立克次体。方法 用鸡胚卵黄囊培养法直接从斑点热疫区一不明热病人血标本中分离立克次体,继之用分子生物学及血清学试验对分离株进行鉴定。结果 从海南省琼中县斑点热疫区一不明热男性民工的血标本中分离到了一株立克次体,命名为ＨＮ－９８株立克次体,西伯利亚种。结论 该结果进一步从病原学上证实海南省琼中县存在有斑点热疫源地。     

海南省澄迈县斑与执群立克次体分离株多间隔序列分型

目的 采用多间隔序列分型（MST）对从海南省澄迈县发热患者及野鼠分离的62株斑点热群立克次体进行分型研究。方法 根据文献检索,应用9对成功用于斑点热群立克次体MST分型引物,对实验62株菌进行PCR扩增及测序。校正后序列进行Blast分析。同时,对序列进行Megalign比对分析单核苷酸多态性（SNPs）。将每株细菌成功测序的6段间隔序列按一定顺序拼接并构建进化树。结果 使用6对间隔序列引物扩增实验菌株,结果显示每对引物扩增序列均显示较大的变异性,共获得48个变异型,以h3为代表的主要变异型占21.7%（13/60）,剩余的47个变异型为独立型,分别占1.6%。进化树分析结果显示48个变异型均归为一簇。同其他参考菌株比较发现,黑龙江立克次体与上述菌株关系密切。SNPs分析发现位点变异主要以T-C转换及A-G转换为主。结论 海南地区斑点热群立克次体分离株非编码间隔序列呈高度变异性。MST分型较传统的血清表型分型以及MLST分型更具有鉴别能力,对未来立克次体暴发流行可提供快速有效的流行株追踪。     

Serosurvey among Mediterranean spotted fever patients of a new spotted fever group rickettsial strain (Bar29)

Mediterranean spotted fever is an endemic disease in Catalonia, Spain. A new spotted fever group (SFG) rickettsial strain (Bar29) of unknown pathogenicity for humans was isolated by our group, in 1996, from the dog brown tick, Rhipicephalus sanguineus. Interestingly, Rickettsia conorii was not isolated in this study. The aim of the present study was to assess the possible pathogenic role of the Bar29 strain. To this purpose, serum samples from 15 patients with Mediterranean spotted fever were obtained and tested by immunofluorescence for antibodies against four related rickettsial strains (R. conorii, R. africae, R. massiliae, and Bar29). Eight of the studied sera reacted at high titers with only R. conorii and Bar29 antigens. For five of the eight sera, the titers against Bar29 were clearly higher than for R. conorii. Four of these sera were also studied by Western blot immunoassay to confirm a specific response. Two of these sera reacted with the high-molecular-mass specific proteins of Bar29 as well as with the low-molecular-mass region (LPS antigen) whereas their reactions with R. conorii were located only on bands of the LPS. This specific response would support the possible pathogenic role of the Bar29 strain for humans. According to this finding, spotted fever caused by R. conorii and rickettsial strain Bar29 may be present in our area. The epidemiological implications of spotted fever caused by R. conorii and by rickettsial strain Bar29 in the Catalonia deserve further studies with isolation and characterization of more rickettsial strains.     

Mediterranean spotted fever: A preliminary tick field study

We studied the prevalence of rickettsia-like organisms infection in different tick species (3154 adults) collected in several areas of the Ebro valley (Spain). The Gimenez stain showed a prevalence of rickettsia-like organisms in 38.6% of the studied ticks. Using the immunofluorescence assay, only two species, Rhipicephalus sanguineus (16.4%) and R. pusillus (19.9%) have shown organisms compatible with spotted fever group rickettsiae.