大兴安岭林区蜱和鼠中莱姆病螺旋体感染及其基因分型研究

目的 了解内蒙古大兴安岭林区蜱和鼠中伯氏疏螺旋体的感染及基因分型情况。方法 应用巢式PCR扩增蜱和鼠中伯氏疏螺旋体5S-23SrRNA间隔区片段，对阳性产物进行限制性片段长度多态性（RFLP）分析和单链构象多态性（SSCP）分析，RFLP分析显示特殊带型的样本测序分析。结果 检测全沟硬蜱1336只，293只阳性，阳性率为21．93％；森林革蜱144只，6只阳性，阳性率为4．17％；嗜群血蜱144只，未发现有伯氏疏螺旋体感染。检测鼠9种145只，感染伯氏疏螺旋体的4种5只，感染率为3．45％；其中检测8只棕背鼠平，2只阳性。RFLP分析及序列分析显示蜱中有B．garinii20047亚型、B．gariniiNT29亚型、B．afzelii基因型以及不同基因型或亚型伯氏疏螺旋体的混合感染；鼠感染的伯氏疏螺旋体包括B．garinii20047亚型和B．gariniiNT29亚型。SSCP分析结果显示带型多于36种。结论 大兴安岭林区蜱及鼠中均存在伯氏疏螺旋体的感染，其中全沟硬蜱的感染率较高；B．garinii型为主要基因型，且该地区伯氏疏螺旋体存在遗传多态性。单只蜱中存在同时感染不同基因型伯氏疏螺旋体的情况，人和宿主动物是否存在不同基因型伯氏疏螺旋体混合感染尚待进一步研究。全沟硬蜱和棕背鼾分别是该林区伯氏疏螺旋体的主要媒介和主要储存宿主。     

伯氏疏螺旋体5S～23SrRNA和D剃基因在浙江省鼠标本检测中的应用

目的探索5S～23SrRNA和ospA基因序列在伯氏疏螺旋体检测中的应用,了解浙江省鼠中感染伯氏疏螺旋体状况。方法用PCR方法,检测磐安县100只鼠标本中5S～23SrRNA和ospA基因特异片段。对检测到的阳性结果进行测序。结果检测100只鼠标本,其中3只鼠标本伯氏疏螺旋体的5S～23SrRNA基因片段为阳性,5只鼠标本伯氏疏螺旋体的ospA基因片段为阳性,与参考核酸序列基本一致。结论 利用ospA和5S～23S rRNA基因能从标本中检测到伯氏疏螺旋体。     

巢式PCR法检测鼠肝脾标本伯氏疏螺旋体

目的应用巢式PCR方法检测鼠肝脾组织中伯氏疏螺旋体外膜蛋白A（ospa）基因,了解淳安县鼠中伯氏疏螺旋体感染情况。方法于2012年8月收集淳安县102份鼠肝脾标本,采用巢式PCR法检测伯氏疏螺旋体ospA基因特异片段,统计标本阳性率。结果在38只黑线姬鼠中检测到伯氏疏螺旋体ospA基因特异片段阳性标本3份,在13只黄毛鼠中检测到伯氏疏螺旋体ospA基因特异片段阳性标本3份,鼠伯氏疏螺旋体总阳性率为5．88％（6／102）。结论淳安县鼠中检测到伯氏疏螺旋体ospA基因片段,有引起蜱媒传染病莱姆病发生的潜在可能,应引起公共卫生部门的重视。     

一组长角血蜱中检出莱姆病螺旋体和斑点热群立克次体复合感染

目的 了解浙江省山区野生动物和蜱中莱姆病、斑点热、埃立克体病(无形体病)的感染情况.方法 采用巢式PCR对采集的鼠、蜱标本进行莱姆病伯氏疏螺旋体、斑点热群立克次体、埃立克体(无形体)特异性核酸片段检测分析.结果 从121份鼠标本和105组蜱标本中检出阳性结果 14份.鼠标本中检出伯氏疏螺旋体5S～23S rDNA间隔区片段1份和埃立克体(无形体)16SrDNA 5'端片段2份.蜱标本中检出阳性11份,包括伯氏疏螺旋体5S～23S rDNA间隔区片段3份和斑点热群立克次体外膜蛋白OmpA基因5'端片段8份.其中1组长角血蜱成虫标本为伯氏疏螺旋体和斑点热群立克次体复合感染,5S～23S rRNA基因间隔区和ompA基因片段均阳性,分别与伯氏疏螺旋体法雷氏基因型和马赛立克次体株等关系较近.结论 在同一组长角血蜱成虫中同时检出莱姆病疏螺旋体和斑点热群立克次体复合感染.     

莱姆病的临床特点及处置要点

莱姆病是由伯氏疏螺旋体(Borrelia burgdorferi)引起的自然疫源性疾病,发病地区不断扩展蔓延,发病率逐年上升,其中,森苏疏螺旋体(B.burgdorferi sensu)、阿氏疏螺旋体(Borrelia afzelii)和加里尼疏螺旋体(Borrelia garinii)等三种基因分型的伯氏疏螺旋体与莱姆病发病密切相关。莱姆病螺旋体基因型的分布与地理环境、媒介生物、宿主动物密切相关,不同基因型引起的临床表现差异巨大。莱姆病临床表现可分为三个阶段：早期局灶期表现为蜱虫叮咬部位的游走性红斑,播散期可出现多发性红斑、螺旋体淋巴细胞瘤、神经系统莱姆病、心肌炎或关节炎,晚期发散期表现为慢性萎缩性关节炎和神经系统损伤症状。     

黑龙江密山口岸三种蜱媒传染病在媒介蜱中复合感染的调查

目的调查黑龙江密山口岸三种蜱媒传染病在媒介蜱中复合感染的情况。方法采集蜱类标本44份,建立伯氏疏螺旋体(Borrelia burgdorferi)、斑点热群立克次体(spotted fever group rickettsia)、嗜吞噬细胞无形体(anaplasma phagocytophilum)三种新发蜱传疾病病原体特异性通用引物,利用PCR方法对所有标本进行特异性片段扩增,对阳性标本测序并进行序列分析。结果在所检测的44份标本中,共检测出伯氏疏螺旋体阳性标本4份,斑点热群立克次体阳性标本6份,嗜吞噬细胞无形体阳性标本2份,感染率分别为13.63%、9.10%和4.55%。在全沟硬蜱检测到两份分别是莱姆病螺旋体与斑点热群立克次体及嗜吞噬细胞无形体和斑点热群立克次体的复合感染,复合感染率为4.55%。结论黑龙江密山地区至少存在两种莱姆病螺旋体(Borrelia garinii,Borrelia afzelii),三种斑点热群立克次体(Rickettsia raoultii,Candidatus Rickettsia tarasevichiae,Rickettsia heilongjiangensis),和嗜吞噬细胞无形体(anaplasma phagocytophilum);全沟硬蜱存在复合感染。     

中俄边境绥芬河口岸鼠类感染伯氏疏螺旋体调查

目的了解中俄边境绥芬河口岸鼠类感染伯氏疏螺旋体的状况及其分子分型。方法 2019年9月用夹夜法在中俄边境绥芬河口岸周边农田、边境巡逻道、驻地及垃圾场捕鼠,采集鼠肾和膀胱组织,提取DNA,用巢式PCR法检测伯氏疏螺旋体,对阳性样本进行基因测序及分析。结果共捕鼠4属5种50只,其中褐家鼠19只、黑线姬鼠21只、大仓鼠3只、大林姬鼠2只、小家鼠5只。从1只黑线姬鼠和1只大仓鼠样本中检测到伯氏疏螺旋体核酸,阳性率为4%。基因序列与伯氏疏螺旋体黑龙江株、云南株的同源性为100%。结论绥芬河口岸地区存在莱姆病传播的风险。     

青海省互助、泽库和祁连县啮齿类动物伯氏疏螺旋体调查

目的调查确定青海省3县啮齿类标本中伯氏疏螺旋体带菌情况。方法从青海省互助、泽库和祁连县共采集啮齿类动物202只,采用巢式PCR方法检测其伯氏疏螺旋体的带菌率。结果采用巢式PCR方法检测啮齿类动物标本202份,阳性49份,伯氏疏螺旋体平均阳性率为24.26%。其中互助县标本共67份,阳性12份,阳性率为17.91%;泽库县标本共78份,阳性27份,阳性率为34.62%;祁连县标本共57只,阳性10份,阳性率为17.54%。3个县的啮齿类动物伯氏疏螺旋体阳性率差异有统计学意义(χ2=7.40,P<0.05)。结论青海省互助、泽库和祁连县啮齿类动物中均存在伯氏疏螺旋体感染,应进一步对当地的媒介和人群进行调查,从而为当地莱姆病的防控提供参考。     

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.     

内蒙古自治区巴彦淖尔地区鼠类携带疏螺旋体调查研究

目的了解内蒙古自治区(内蒙古)巴彦淖尔地区鼠类分布、疏螺旋体感染及其基因型等,为该地疫情防控和风险评估提供基础数据。方法于2015-2016年每年的4-6月、9-10月采用夹夜法捕获鼠类,采用特异性PCR扩增法对标本进行疏螺旋体检测,并通过测序和序列比对等进行疏螺旋体基因型分析。结果共捕获鼠类480只,其中子午沙鼠(174只)和长爪沙鼠(124只)数量居多,为该地优势鼠种。鼠类脾脏标本经PCR检测,共发现8份疏螺旋体fla B和16S rDNA基因阳性标本,阳性率为1.67%,其中毛足鼠和长爪沙鼠的阳性率分别为7.14%(2/28)和4.84%(6/124)。对阳性标本基因片段进行序列分析发现,感染的疏螺旋体为Borrelia afzelii和B.garinii。结论内蒙古巴彦淖尔地区鼠类携带的疏螺旋体以B.afzelii和B.garinii为主,应加强该病原体的检测和莱姆病防制。     

Prevalence of Borrelia burgdorferi sensu lato genospecies in host-seeking Ixodes ricinus ticks in selected South Bohemian locations (Czech Republic)

In selected localities of Ceské Bud?jovice and Cesky, Krumlov districts, well known by stable high incidence of tick-borne encephalitis (TBE) human cases but with low incidence of Lyme borreliosis, monitoring of Borrelia burgdorferi sensu lato (s.l.) in Ixodes ricinus ticks was performed. Research was also aimed at the spread of I. ricinus to mountain areas of this region (National Park Sumava), as well as at investigating this tick for B. burgdorferi s.l. genospecies and TBE virus infection. Altogether 498 nymphs, 88 females and 11 males of I. ricinus from lower locations and 58 nymphs from mountain locations (760-1080 m above sea level) were tested by polymerase chain reaction. In lower locations total prevalence of Borrelia burgdorferi s.l. in Ixodes ricinus ticks was 35%. Single infection of Borrelia afzelii, B. garinii and B. burgdorferi sensu stricto (s.s.) was found in 59, 50 and 63 ticks, respectively (i.e. in 12.8, 11.2 and 14.1%). Double infection was found in 42 ticks (6.0%) and triple infection in three ticks (0.4%). The high frequency of B. burgdorferi s.s. exceeds the as yet reported occurrence in Central Europe. These circumstances are discussed. In mountain locations B. afzelii was found in five ticks, that including two co-infection with B. garinii, in elevations of 762 m and 1024 m above sea level, respectively. This fact signals a real danger of human infections in a region that was previously deemed to be without risk. Moreover, this region is more and more the target destination of tourist activities. The results also suggest that the penetration of infection can be rapid and formation and establishment of natural focus of Lyme borreliosis might be rather quick.     

用聚合酶链方法对北京林区莱姆病疫源地及莱姆病病原体基因型的探索性研究

目的：进一步明确北京林区是否存在莱姆病的自然疫源地及其分布，方法基于莱姆病螺旋体外膜蛋白A基因建立半巢式聚合酶链式反应(polymerase chain reactio,PCR)方法，对从北京6个林区采集的蜱和鼠进行检测和基因分型，选择阳性标准本进行克隆和序列测定，与已知序进行同源性比较，间接免疫荧光法检测抗莱姆病螺旋体IgG抗体，从长角血蜱中分离莱姆病螺旋体。结果：从门头沟区东灵山采集的标本中检测到莱姆病螺旋体DNA片段，3只游离全沟硬蜱1只检测阳性，57只寄全沟硬蜱若蜱中1只检测阳性；119只野鼠中9只检测阳性，其中8只，B.garinii阳性，1只B.afzelii阳性。50份野鼠血清有5份莱姆病螺旋体IgG抗体阳性，采集采的160只长角血蜱（20只／组）。未分离到莱姆病螺旋体菌株。结论：北京门头沟区东灵山可能存在莱姆病的自然疫源地，包括两个基因型，全沟硬蜱可能是莱姆病的传播媒体，野鼠可能是贮存宿主。     

浙江省在鼠类中检测到伯氏疏螺旋体ospA基因

目的了解浙江省磐安县鼠中感染伯氏疏螺旋体的情况,研究以外膜蛋白A(OspA)为靶基因的PCR方法在浙江省的应用。方法利用PCR方法,检测磐安县128份鼠肝、脾标本中ospA基因特异片段;对所检测到的阳性结果进行序列测定,并进行分析。结果从128份鼠肝、脾标本中检测发现4例ospA基因阳性片段,其中3份来自黄毛鼠,1份来自大林姬鼠;核酸序列基本一致,与伯氏疏螺旋体法雷斯疏螺旋体高度相似。结论利用ospA基因能从标本中检测到伯氏疏螺旋体;浙江省部分山区存在鼠感染伯氏疏螺旋体的情况,其中伯氏疏螺旋体法雷斯疏螺旋体占优势。     

Dogs as sentinels for Lyme disease in Massachusetts.

BACKGROUND. An investigation of the relationship between incident human cases of Lyme disease and seroprevalence of antibodies to B. burgdorferi in dogs was undertaken in order to determine whether dogs might serve as sentinels for Lyme disease. METHODS. 3011 canine serum samples were analyzed by ELISA for antibody to B. burgdorferi. Records of incident human cases of Lyme disease were obtained from the Massachusetts Department of Public Health. RESULTS. Regression analyses of the relationship between the log10 (mean incidence in people 1985-1989) and canine seroprevalence from July 1988-August 1989 revealed that canine seroprevalence was highly predictive of incidence (R2 = 0.86, p less than .0001). A logistic regression model that incorporates the altitude of the town where each dog was resident, the date of sampling, and information on each dog's age, sex, and breed adequately explained the risk of canine seropositivity. Dogs resident at altitudes less than 200 feet, of sporting or large mixed breeds, and greater than two years of age were five times, four times, and almost three times more likely, respectively, to exhibit seropositivity than were other dogs. CONCLUSIONS. Estimates of the prevalence of antibody to B. burgdorferi in dog populations offers a sensitive, reliable, and convenient measure of the potential risk to people of B. burgdorferi in the environment. Risk factors for canine seropositivity may directly or indirectly illuminate certain aspects of the epidemiology of human Lyme disease.     

The distribution and prevalence of B. burgdorferi genomospecies in Ixodes ricinus ticks in Ireland

Questing Ixodes ricinus ticks were collected from six locations throughout Ireland and 638 nymphs, 111 females and 118 males were investigated for infection with Borrelia burgdorferi sensu lato (s.l.). The total prevalence of B. burgdorferi s.l. in the ticks was determined as 14.9% by polymerase chain reaction (PCR) amplification of the spacer region of 5S-23S rRNA genes. Infection prevalence was significantly higher in adult (20.1%) Ixodes ricinus compared to nymphs (13.1%). The prevalence of infection in adult male and female ticks was similar (19.5% and 20.7% respectively). The genomospecies B. burgdorferi sensu stricto, B. afzelii, B. garinii and group VS116 were identified by reverse line blot (RLB) using genomospecies specific oligonucleotide probes. The most prevalent B. burgdorferi genomospecies identified were VS116 (34.6%), B. garinii (24.3%) and B. burgdorferi sensu stricto (18.4%). B. afzelii was uncommon (6.6%). Multiple infections were observed in 13.2% of the infected ticks. The distribution of the genomospecies showed geographical variation and also seemed to be influenced by the nature of the habitat. A broad range of genomospecies seemed to be associated with the presence of a wide spectrum of potential reservoir hosts in the habitat and also with a high overall prevalence of B. burgdorferi s.l.     

Seroepidemiology of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum in wild mice captured in northern Turkey

An expedition across the Asian part of the Black Sea coast and national parks of Northern Turkey was organized in the summer of 2001 to investigate the presence of Borrelia burgdorferi sensu lato (s.l.), Lyme borreliosis agent, and Anaplasma phagocytophilum, human granulocytic ehrlichiosis, agent, in wild mice. A total of 65 Apodemus flavicollis, Apodemus sylvaticus, Microtus epiroticus, Crocidura suaveolens and Mus macedonicus, were captured. Two out of 22 Apodemus sylvaticus specimens were seropositive for B. afzelii by enzyme-linked immunosorbent assay as confirmed by Western blotting, however cultures of skin and bladder samples from all small mammals in Barbour-Stoenner-Kelly's medium-II remained negative for B. burgdorferi s.l. All sera tested were negative for Anaplasma phagocytophilum by indirect immunofluorescent assay. The prevalence of B. burgdorferi s.l. and Anaplasma phagocytophilum is low in wild mice of the Asian part of Northern Turkey.     

Detection of four Borrelia burgdorferi genospecies and first report of human granulocytic ehrlichiosis agent in Ixodes ricinus ticks collected in central Italy

The presence of Borrelia burgdorferi s.l. and of Ehrlichia phagocytophila group was sought by PCR in Ixodes ricinus collected in a protected area of central Italy. Nymphs (n = 1475, gathered in 295 pools of 5 nymphs each) and adult ticks (n = 28) were examined. B. burgdorferi s.l. was detected in 13.8% of the nymph pools; of these, 63.4% were infected by B. valaisiana, 26.8% by B. afzelii, 7.3% by B. garinii, and 2.5% by B. burgdorferi s.s. Only a single adult male tick proved to host B. afzelii. The agent of human granulocytic ehrlichiosis (HGE) was detected in 2.7% of the nymph pools. Two HGE agent-positive nymph pools were also found to be positive for B. garinii and for B. afzelii, respectively. This is the first report from central Italy of the finding of the HGE agent in ticks.     

Protection against tick-transmitted Lyme disease in dogs vaccinated with a multiantigenic vaccine

In an effort to develop a safe and effective vaccine for the prevention of Lyme borreliosis that addresses concerns raised over currently available vaccines, dogs were vaccinated twice with a multiantigenic preparation of Borrelia burgdorferi, strain N40, on days 0 and 20 of the experiment. About 70 and 154 days after the first immunization, dogs were challenged by exposing them to field-collected Ixodes scapularis ticks harboring B. burgdorferi. Vaccinated dogs were completely protected from infection by all criteria utilized to assess infection, developed high-titer anti-B. burgdorferi serum antibodies and growth inhibitory activity which persisted for over 200 days, and did not demonstrate any untoward consequence of vaccination. Serum absorption experiments revealed that borreliacidal and most likely protective antibodies in dogs receiving the multiantigenic preparation were not only elicited against the OspA antigen, but were also produced against additional yet to be determined targets on B. burgdorferi organisms. These data demonstrate that a multiantigenic vaccine is effective in preventing Lyme disease transmitted via the natural vector.     

Prevalence of Lyme borreliosis in The Netherlands]

In the autumn of 1989 a seroepidemiological study was carried out among 440 owners of hunting dogs and 1052 blood donors from different regions in the Netherlands. To detect IgG antibodies to Borrelia burgdorferi an enzyme-linked immunosorbent assay was performed. The prevalence of antibodies to B. burgdorferi in owners of hunting dogs was 15%, which was significantly higher than in blood donors (9%). In both groups the prevalence of seropositivity increased with age. There was no difference between men and women. The prevalence of antibodies to B. burgdorferi in blood donors from different regions varied significantly, ranging from 2% to 17%. Only 3% of the owners of hunting dogs could recall having had symptoms most likely to be due to Lyme borreliosis. Of the 68 seropositive hunters 64 (94%) were asymptomatic. The results of this study indicate that in the Netherlands asymptomatic infections with B. burgdorferi are common in individuals highly exposed to ticks and that there is considerable variation in the prevalence of seropositivity in the general population. Hence caution is called for in the clinical interpretation of IgG test results.     

从桂黔交界地区中华硬蜱中分离到莱姆病螺旋体

目的从桂黔交界地区捕获的蜱中分离莱姆病螺旋体,以探查广西壮族自治区（广西区）和贵州省莱姆病的传播媒介。方法用BSK-Ⅱ培养基从蜱中分离莱姆病螺旋体。用PCR扩增分离菌株的5S～23SrRNA基因间隔区,将PCR扩增产物克隆后测序,通过将测序结果与基因库中莱姆病螺旋体菌株的5S～23SrRNA基因间隔区进行同源性比较和分析,从而鉴定分离株的基因型。结果从捕获的中华硬蜱中分离出1株莱姆病螺旋体（命名为QLT1）。分离株经鉴定为Borrelia valaisiana基因型莱姆病螺旋体。结论中华硬蜱很有可能是广西区和贵州省莱姆病的传播媒介。