Scrub typhus--one case report

Scrub typhus (tsutsugamushi disease) is an acute infectious disease caused by Rickettsia tsutsugamushi transmitted through the bite of larvae of certain trombiculid mites. Geographical distribution in Asian-Pacific region is much of the roughly triangular area bounded by Japan, Pakistan and Australia. It is an endemic illness in the Pescadores Islands, but has scarcely been reported in central Taiwan. An eleven-year-old boy was admitted to Changhua Christian Hospital with the chief complaints of fever, lethargy and skin rash for seven days. On physical examination, he was found to have painless eschar, conjunctivitis, meningoencephalitis, pneumonitis, ascites, jaundice, hepatomegaly, liver function impairment and thrombocytopenia. His Proteus OX-K agglutinin titer increased from 1:160 in the acute sera to 1:640 in the convalescent sera. A greater than four-fold rise (greater than 1:640) in antibody titers to Karp, Gilliam, Kato strains of R. tsutsugamushi between acute and convalescent sera were demonstrated by immunofluorescent antibody. The patient was treated with minocycline and chloramphenicol and was completely recovered.     

江苏省几种主要类型人畜立克次体抗体阳性检出情况的现况调查

目的了解江苏省人畜立克次体感染的主要类型、抗体阳性检出率及感染的可能影响因素。方法按地理位置,选择江苏省溧水县、沛县、盱眙县、宜兴市和滨海县的5个调查点,采用间接免疫荧光法检测莫氏立克次体（RM）、黑龙江立克次体/西伯利亚立克次体（RH/RS）、恙虫病东方体（OT）、贝氏柯克斯体（CB）、横赛巴尔通体/五日热巴尔通体（BH/BQ）、查菲埃立克体（HME）及人粒细胞无形体（HGA）等7种常见立克次体血清IgG或IgM抗体。结果 5个调查点共取血样2 562份,人群病原体检测率最高的是BH/BQ（24.8%）。男性中HGA和BH/BQ抗体阳性检出率高于女性,其余的检出率是女性高于男性;除了RH/RS外,其余立克次体分布均存在地区差异（均P〈0.01）。动物中7种立克次体的抗体均检出,其中OT阳性率最高（31.8%）,主要是在羊体内,且存在地区间差异（均P〈0.01）。多因素分析发现,影响立克次体抗体阳性率的因素有年龄、性别、地区和蜱/螨叮咬史。结论江苏省农业人群及家畜存在多种立克次体感染,以RM、BH/BQ、CB为多。     

山东省沂源县西部地区恙虫病东方体、地方性斑疹伤寒和斑点热立克次体血清流行病学的初步研究

目的 了解近年山东省沂源县西部地区农村人口恙虫病东方体、地方性斑疹伤寒立克次体和斑点热立克次体的感染情况,为自然疫源性疾病的预防和控制提供依据。方法 2011年从山东省沂源县西部乡镇的农村人口中随机收集192份血清,采用间接免疫荧光法检测血清中恙虫病东方体、地方性斑疹伤寒立克次体和斑点热立克次体抗体。结果 恙虫病东方体、地方性斑疹伤寒立克次体和斑点热立克次体抗体血清阳性率分别为56.77%(109/192)、79.69%(153/192)和69.79%(134/192)。结论 山东省沂源县西部农村人口中恙虫病东方体、地方性斑疹伤寒立克次体和斑点热立克次体的感染率较高。     

Leptotrombidium scutellare in transmission of epidemic hemorrhagic fever virus]

To further elucidate the role of Leptotrombidium scutellare in transmission of epidemic hemorrhagic fever virus (EHFV), a series of studies were carried out from 1988 to 1990. EHFV was isolated from both larvae of free mites collected from the grassland of endemic areas and larvae of filial mites hatched in the laboratory. The suckling mice bitten by these larvae were infected by EHFV. Because only the larvae of chigger mite can bite vertebrate hosts and only take a full meal in its entire life cycle, the pathogen carried by it can only be originated from its parent mite via transovarial route. Thus it can be confirmed that the natural infection of EHFV in these mites is transferred via transovarial transmission. The results demonstrate that L (L.) scutellare can naturally be infected by EHFV; EHFV can be transmitted to the vertebrate host by biting of the larvae and can be transferred via transovarial transmission in mites; and therefore, L (L.) scutellare can serve as a transmitting vector of EHF.     

Natural foci of tsutsugamushi disease in the Nan Peng Lie Islands in China

目的：近年我国南潮列遍恙虫病率明显增高,而国内并无该地区恙虫病疫源地的记载,为当地人民的健康,本研究对该地区作为恙虫病疫源地进行全面调查与研究。方法：疫源地流行病学调查,病原分离,当地预防措施的制定。结果：该地区为南亚热带岛屿疫源地,主要宿主为褐家鼠,其季节消长与发病一致。主要媒介为地里纤恙螨,褐家鼠带螨率、地里纤恙螨的季节消长与发病均一致。从宿主与媒介分离35株恙虫病立克次体,鉴定7株大部分为Karp株。血清流行病学调查表明该岛居民恙虫病抗体阳性率极高。预防措施应用以后发病率降低。结论：这是第一次成功地证明我国南澎列岛是恙虫病疫源地。     

海南岛立克次体血清学和病原学调查报告

目的:调查海南岛立克次体的群别及其分布。方法:应用微量免疫荧光检测法(mIFA)对人群血清进行恙虫病、斑疹伤寒和斑点热3种立克次体IgM、IgC抗体检测。应用L929单层细胞进行立克次体分离培养。立克次体用特异性抗体进行mIFA鉴定。结果:恙虫病、斑疹伤寒和斑点热3种立克次体ISC抗体阳性率分别是13.55％(76/561),18.77％(101/538),30.83％(164/532)。其中IgM和IgC抗体均≥1:80者,斑疹伤寒为32.08％,斑点热为46.30％。立克次体分离培养结果,20份不明原因发热或疑似立克次体病患者血液标本分离出12株立克次体,免疫血清mIFA鉴定及聚合酶链反应(PCR)技术检测立克次体特异性DNA等方法鉴定出3株恙虫病立克次体、2株斑疹伤寒立克次体和7株斑点热群立克次体。结论:海南岛确有恙虫病、斑疹伤寒、斑点热病存在,该岛的中、西部感染率较高,南、北部较低。     

海南省发热患者血标本中恙虫病东方体groEL基因检测

目的了解海南省发热病人中感染恙虫病东方体的状况,并确定其基因分型。方法利用巢氏PCR方法,检测海南省各家医院2009~2010年送检的117份不明原因发热病人血标本的groEL基因的特异性片段,对所检测到的部分目的片段进行基因测序,从基因水平进一步证实阳性结果,并对序列同源性及进化分析。结果从117份发热病人血标本中发现有恙虫病东方体阳性15份,检出率为12.8%。取10份PCR阳性产物进行测序,核酸序列基本一致,彼此间仅存在3个核苷酸的差异,构建进化树进行聚类分析,结果示海南省恙虫病东方体序列与R.tsutsugamushi(M31887)恙虫病东方体在同一分支上,同源性高。结论海南省发热病人中存在恙虫病东方体感染的状况,应加强相关监测和防控措施,为给海南省制定恙虫病防治策略提供科学依据。     

应用L929细胞从患者血液中分离立克次体

目的:从不明原因发热患者血液中分离立克次体。方法:应用L929细胞培养法分离立克次体,并用微量免疫荧光检测法(mIFA)、聚合酶链反应(PCR)技术进行鉴定。结果:从20份不明原因发热患者血液标本中分离出12株立克次体,鉴定结果,3株为恙虫病立克次体,2株为斑疹伤寒立克次体,7株为斑点热群立克次体。结论:应用L929细胞培养法可以直接从立克次体病患者血液中分离立克次体。     

中国恙螨新种及新纪录名录

恙螨是一大类小型节肢动物的统称,在动物分类学上隶属于节肢动物门、蛛形纲、蜱螨亚纲、真螨目的恙螨科和列恙螨科。恙螨幼虫可以通过直接叮咬宿主动物引起恙螨性皮炎,还能作为传播媒介传播恙虫病（丛林斑疹伤寒）和肾综合征出血热（流行性出血热）等人兽共患病和虫媒传染病。《中国恙螨》详细记录了1997年以前的在中国发现并定种的恙螨,总共3个亚科46属452种。为了给基础研究和疾病防控提供参考,本文结合近年的研究成果和经验,对1960至2021年的文献涉及内容进行分析和甄别,新增2属74种恙螨,中国恙螨的种类达到了3个亚科48属527种恙螨。     

用国产羟基磷灰石纯化抗恙虫立克次体单克隆抗体

用国产羟基磷灰石层析柱分别提纯含抗恙虫立克次体单克隆抗体 Kp3(IgG_1)及 Kp4(IgM)的小鼠腹水,回收率较用蛋白 A 琼脂糖层析或 DEAE-纤维素离子交换层析为高。且抗体活性稳定.     

恙虫病并发多脏器损害167例临床分析

目的探讨深圳地区恙虫病并发多脏器损害的特征及误诊情况。方法对1990年9月至2004年11月深圳地区收治的恙虫病并发多脏器损害167例患者进行回顾性分析。结果3个器官损害92例，占55．1％；4个器官损害46例，占27．5%；5个器官损害24例，占14．4％；6个以上器官损害5例，占3．0％。在器官损害方面肝脏损害最常见，为73．7％（123／167），其次为肺损害，为58．6%（98／167），心脏损害和肾脏损害也较常见，分别为52．7％（88／167）、35．9%（60／167）。病情危重程度与器官损害数目成正相关。及时诊治，预后良好，治愈率94．6%。9例因基础疾病或诊治延误合并多器官功能障碍（MODS）死亡，病死率5．4％。结论恙虫病临床表现复杂多样，常伴发多器官损害，其中以肝脏、肺、心脏和肾脏损害最常见，应仔细分析病情，及时正确诊治。     

人感染立克次体致病研究现状

立克次体病是由人感染立克次体后引起的一系列如斑点热、斑疹伤寒、恙虫病、埃立克次体病、人粒细胞无形体病等急性发热性疾病,感染早期表现为发热、皮疹、头痛、肌肉酸痛、淋巴结肿大等,晚期可因心肌炎、脑炎、肺栓塞、静脉血栓形成、出血、休克、呼吸衰竭、肝肾衰竭和心力衰竭等严重并发症导致死亡。立克次体病随着交通运输、畜牧养殖、进出口贸易、旅游等产业的发展在全世界范围内广泛传播。检测技术随着分子生物学水平的发展,其灵敏度和特异度不断提高,治疗方案也不断被完善。为有效防控立克次体病的发生、发展和流行,保护人类的健康,本综述就人感染立克次体致病的流行病学调查、立克次体致病现状、临床和实验室诊断方法、治疗进展等进行归纳中介,以提高广大研究者对此类虫媒疾病的认识。     

红水河龙滩水库拟淹没区人群立克次氏体病血清流行病学调查

1987年3～5月,研究者对拟建红水河龙滩水库淹没区人群进行血清流行病学调查,结果发现人群中立克次氏体病感染率较高。788份健康人血清中斑疹伤寒阳性者为309份(39.21％),恙虫病阳性者13份(1.65％),Q热阳性者33份(4.19％)。x~2检验表明。不同年龄、性别、职业人群上述3种病的血清抗体阳性率无显著性差异。但不同地区人群的斑疹伤寒感染率有显著性差异。     

海南岛恙虫病立克次体研究

目的:阐明海南岛恙虫病立克次体的存在及其分布。方法:①恙虫病立克次体血清学调查用微量免疫荧光检测法(mIFA)。②恙虫病立克次体分离用小鼠接种法和L929细胞培养法,恙虫病立克次体鉴定用特异性抗体mIFA。③应用聚合酶链反应(PCR、NPCR)技术检测恙虫病立克次体特异性DNA。④DNA序列。结果:①35份不明原因发热患者血清中,10/35(28.57％)份血清呈IgG抗体阳性反应(滴度≥1:80)。收集自海南岛的东、西、南、北、中部地区的561份人群血清恙虫病立克次体IgG抗体阳性率为13.55％(76/561)。其中东部地区阳性率为8.69％(10/115),南部为7.22％(7/97),西部为28.83％(32/111),北部为11.76％(12/102),中部为11.03％(15/136)。②小白鼠接种分离法从疑似立克次体病患者血液中分离出3株恙虫病立克次体,L929细胞培养法从20份不明原因发热患者血液中分离出3株恙虫病立克次体。③应用PCR技术从9例疑似立克次体感染患者血液中检出4例恙虫病立克次体特异性DNA。用NPCR法从17组野鼠脾脏标本中检出3组恙虫病立克次体特异性DNA。④DNA序列已经分析清楚。结论:海南岛确有恙虫病存在,该岛的中、西部感染率较高,南、北部较低。海南岛恙虫病立克次体DNA序列已分析清楚。     

小儿恙虫病35例临床特征分析

目的 探讨小儿恙虫病临床特征并对本病的治疗效果进行分析.方法 对海南省人民医院2008年1月至2010年12月收住的35例恙虫病的临床资料进行回顾性分析.结果 35例患儿均有发热,均发现有焦痂或溃疡;外周血象＜4.0×109/L以下者9例,血红蛋白＜90g/L者26例,血小板＜100×109/L者23例;变形杆菌OXK凝集效价阳性率54.29％;肝功能损伤33例;心肌损伤11例;并发脑炎7例.治疗效果:痊愈31例,好转3例,死亡1例.结论 恙虫病可累及肝、肺、心脏、血液、神经等器官、系统,外斐反应阳性率不高,作为诊断或排除本病的可靠性有限.结合流行病学史及焦痂或特异性溃疡是确诊恙虫病的最重要依据.     

鲁豫两省恙虫病东方体感染流行病学Meta分析

目的:综合分析山东、河南两省恙虫病流行病学特征,对防治本病提供科学依据。方法:采用Meta分析法对两省发表的恙虫病和恙虫病东方体(Ot)感染相关资料进行汇总、归纳和统计分析。结果:共检索105篇文献,从血清学和流行病学或分子生物学证实山东、河南两省存在恙虫病自然疫源地。山东疫情波及40余县市,河南省波及15个县市。患者分布广泛,农民为主占80%以上,青壮年为主;发病高峰在10月,属秋冬型;临床特征与南方恙虫病有相似,但各地仍有一定差异;山东省认为黑线姬鼠和小盾纤恙螨是主要宿主和主要传播媒介。结论:在山东和河南两省恙虫病患者分布广,疫区呈逐渐扩展趋势,开展本病的防治研究具有明显社会效益和重要军事学意义。     

Regional prevalence and transmission route of Kaposi’s sarcoma-associated herpes virus in Zhejiang, China

Background  The infection of Kaposi’s sarcoma-associated herpes virus (KSHV) is most likely the cause of clinical Kaposi’s sarcoma, primary effusion lymphoma, and multi-center Castleman’s disease. KSHV infection has very limited epidemiological survey data in China, and its definite mode of transmission remains controversial. This study aimed to determine the infection status and the main transmission route of KSHV in Chinese population.

Methods  An enzyme-linked immunosorbent assay (ELISA) utilizing KSHV ORF65 recombinant protein was employed to analyze the antibody response to KSHV ORF65 in sera from 122 healthy physical examination people, 107 intravenous drug users, 135 non-intravenous drug users, 211 hepatitis B (HBV) patients infected via blood transmission, 107 kidney transplant recipients, and 72 female sex workers in Zhejiang Province in Southeast China.

Results  KSHV infection occurred relatively common (13.1%) in healthy population in Zhejiang, China. Infection rate was 16.7% in female sex workers, but significantly elevated in intravenous drug addicts (58.9%), blood-transmitted HBV patients (28.0%) and kidney transplant patients (41.1%).

Conclusion  Blood borne transmission of KSHV is probably the main route of infection in Zhejiang Province.

     

Queensland tick typhus in Sydney: a new endemic focus.

A new endemic focus of Queensland tick typhus was defined when two cases of Rickettsia australis infection were recognized in Sydney. Although the tick vector is distributed throughout coastal, eastern Australia these are the first cases diagnosed south of Lismore, New South Wales.     

Protective immunity in mice elicited by living infective third-stage hookworm larvae (Shanghai strain of Ancylostoma caninum).

OBJECTIVE: To elucidate the mechanisms of protective immunity in mice elicited by living hookworm (Ancylostoma caninum third-stage infective larvae (L3). METHODS: The number of migrating infective larvae recovered from the lungs was used as an endpoint for vaccine immunity. The timing of maximal L3 lung entry was determined by counting the number of lung larvae at several time points after infection with 500 or 1000 L3. Mice were immunized either orally or subcutaneously with 500 L3, followed by two boosts of L3 once every two weeks. The immunized mice were challenged orally with 500 L3 one week after the final boost. To evaluate the protective immunity, the number of L3 recovered from the lungs of the immunized mice during the time of maximal larval entry was compared with that of controls. Host immunity was also evaluated by comparing circulating anti-L3 antibodies between immunized and controlled mice, using both enzyme immunoassays and immunoblotting techniques, and by lung histopathology. RESULTS: The peak time of larval entry into the lungs occurred 48 hours after infection. Mice immunized either orally or subcutaneously with L3 exhibited a marked reduction (90.2% and 86.2% respectively) in the number of recovered lung larvae in comparison to controls (P < 0.01). The protection might be associated with circulating anti-L3 antibodies, including antibodies directed against 132-200 kDa L3 antigens, as well as three major antigens ranging from 28 to 51 kDa. Larvae migrating through the lungs of vaccinated mice showed cuticular damages accompanied with host-inflammatory cell invasion. CONCLUSIONS: Immunization with living L3 protects mice against lung invasion after challenged with hookworm infection. Vaccine immunity is associated with circulating antibodies against L3 antigens and lung inflammatory responses. The mouse model is potentially useful for developing a hookworm vaccine.     

广州管圆线虫V期幼虫cDNA表达文库中优势诊断抗原的筛选、鉴定和克隆

目的筛选与广州管圆线虫感染小鼠血清具有较强免疫反应性的优势诊断抗原。方法用感染广州管圆线虫21d的小鼠感染血清做免疫探针筛选广州管圆线虫v期幼虫cDNA表达文库,对筛选得到的阳性克隆进行插入片段的测序和生物信息学分析,再根据测序结果设计引物扩增该基因并将其克隆入PET-30a（＋）载体中。结果共获得6个阳性克隆,经DNA测序及同源性分析表明,发现其中2个与广州管圆线虫髓鞘转录因子1（MYT1）高度同源,1个与广州管圆线虫胶原蛋白家族基因（alpha-collagen）高度同源,且均为全长cDNA。克隆出广州管圆线虫MYT1全长cDNA序列．构建的新基因重组质粒经双酶切后证明含有与目的片段长度相符合的目的片段。结论用感染小鼠血清作为探针初步筛选到2个广州管圆线虫基因,并成功构建MYT1的原核表达重组质粒PET30a（＋）-MYT1。