我国巴贝虫病流行现状与研究进展

巴贝虫病是由巴贝虫感染引起的一类人兽共患寄生虫病。巴贝虫经蜱叮咬、输血或器官移植等途径传播,主要寄生于人或其他脊椎动物红细胞内。感染人体的巴贝虫主要有田鼠巴贝虫、猎户巴贝虫、邓肯巴贝虫、分歧巴贝虫等。巴贝虫病呈世界性分布,多发于夏秋季节,在我国属于新发、罕见寄生虫病。过去临床上缺乏敏感有效的诊断方法,导致很多巴贝虫病患者未能得到及时治疗。随着高敏感性的分子生物学检测技术在临床上的应用,巴贝虫病病例报告数量逐渐增多。本文详细回顾了1943年至今我国人巴贝虫病病例报告情况,概述了巴贝虫病诊断、治疗和致病机制等方面的研究进展,分析了我国巴贝虫病防控的挑战和前景。     

人巴贝虫病研究进展

巴贝虫病是巴贝虫在红细胞内寄生导致的一种人畜共患寄生虫病.人巴贝虫病主要由田鼠巴贝虫（Babesia microti）、B.duncani、分歧巴贝虫（B.divergens）、B.venatorum等引起,病例呈世界性分布.其传播方式有蜱虫叮咬、输血及母婴传播等.患病症状与疟疾相似,典型的临床症状表现为发热、肌痛、贫血、血红蛋白尿、黄疸等,其严重程度主要取决于自身免疫状况和感染巴贝虫的种类.巴贝虫病常见的诊断方法为涂片染色法、动物接种法、血清学检测法以及分子生物学检测法.     

国内外巴贝虫病流行现状与研究进展

巴贝虫病是一种新发寄生虫病，在全球包括欧洲、亚洲、非洲、南美洲、北美洲及澳洲等地区均有流行，美国是巴贝虫病病例数最多的国家。我国巴贝虫病主要分布在东北地区，其次是西南地区。作为一种新发虫媒传染病，该病对人类健康造成严重威胁，但研究基础相对薄弱，应引起足够重视。巴贝虫病相关研究重点主要包括巴贝虫病诊断抗原筛选、巴贝虫与宿主及其他病原体共感染互作机制。本文就目前国内外巴贝虫病流行分布情况、巴贝虫病诊断抗原筛选、宿主免疫应答机制及共感染现象等研究热点进行综述。     

田鼠巴贝虫病的诊断技术研究进展

田鼠巴贝虫是引起人兽共患巴贝虫病的主要病原体之一.在全球散发的人巴贝虫病例报道中时常诊断出该病原体的存在.因此,由该病原体引起的人巴贝虫病逐渐引起了人们的重视,促进了对田鼠巴贝虫病的诊断研究.本文就目前国内外关于田鼠巴贝虫病的病原、分子生物学和免疫学诊断技术的最新进展做一综述.     

1例人感染田鼠巴贝虫的实验室诊断及文献复习

目的 回顾1例反复发热半年,最终确诊为田鼠巴贝虫感染的诊断过程,复习文献,为巴贝虫病的诊断提供参考. 方法 收集患者的临床资料和流行病学资料,采集患者骨髓和外周血涂片镜检,抽提血液基因组DNA,用田鼠巴贝虫特异引物进行巢式PCR扩增,取血清进行间接免疫荧光检测. 结果 骨髓和外周血涂片镜检可见少量红细胞内有环状体,未见其它疟原虫红细胞内期形态.巢式PCR获得阳性条带,经测序证实为田鼠巴贝虫18s rRNA基因;间接免疫荧光抗体试验阳性;经克林霉素、磷酸氯喹片抗巴贝虫治疗2个疗程,患者达到临床治愈. 结论 综合患者临床资料、实验室检查结果、以及抗巴贝虫药物疗效,确诊1例人田鼠巴贝虫感染病例.在病原学检查不典型时,分子生物学和免疫学检查结果是重要的巴贝虫病诊断依据.     

田鼠巴贝虫病诊断方法的研究进展北大核心CSCD

田鼠巴贝虫病是一种与疟疾相似的人兽共患血液寄生虫病,主要分布于美国、欧洲和亚洲等国家和地区。田鼠巴贝虫病的诊断方法种类繁多,但目前大多仍处于初期探索阶段。本文对现有的人感染田鼠巴贝虫病的主要诊断方法和存在的问题作一简要综述。     

一种正在传播的寄生虫病——人巴贝虫病

巴贝虫病是一种由巴贝虫引起脊椎动物寄生虫病。1888年巴贝首次在牛血肉发现该病的病原体B.divezgens。巴贝虫病主要在家养和野生的哺乳动     

人巴贝虫病研究进展

巴贝虫病是由RBC内寄生的巴贝虫属(Babesia)通过硬蜱叮咬感染所致的人兽共患寄生虫病,可通过输血和母婴途径传播.人巴贝虫病的临床表现轻重不一,从亚临床感染、轻度流行性感冒样症状直至危及生命等,高龄、脾脏切除者和免疫功能缺陷者易重症化.自1957年发现首例人巴贝虫病以来,全球已发现几百例感染者,而实际感染数量更高.我国硬蜱种类较多,随着人们户外活动增加,与蜱虫接触的机会加大,蜱传播疾病增加趋势明显,且巴贝虫病与莱姆病及人粒细胞无形体病存在混合感染.了解巴贝虫病对于蜱传播疾病的防治很有必要,本文对巴贝虫病新近研究进展综述如下.     

广西壮族自治区犬巴贝虫感染现状调查

目的 分析广西壮族自治区犬巴贝虫病的流行情况. 方法 在广西的玉林、北海、南宁、百色和河池等地区的17个采样点,用FTA试纸卡采集犬血.巢式PCR特异性扩增巴贝虫18s rDNA基因,纯化阳性样本的PCR产物、测序,与GenBank中的巴贝虫序列进行比对.应用Mega5.1软件构建系统发育树,分析系统发生关系. 结果 共采获87份犬血,其中阳性血样11份,感染率为12.64％ （11/87）.11份阳性血样的巴贝虫序列相同,与GenBank中的佛氏巴贝虫（Babesia canis vo-geli的同源性为98.1％.在邻接法构建的系统进化树上,犬血样中检测到的巴贝虫与佛氏巴贝虫同属一个分枝,系统发生关系近. 结论 广西犬血中检测到的巴贝虫与GenBank中的佛氏巴贝虫同源性高,为佛氏巴贝虫.     

巴贝虫和巴贝虫病的研究进展

巴贝虫(Babesia spp.)是一种人畜共患的血液寄生虫,主要由蜱传播,呈世界性分布,国内外均有人体感染的报道,人感染巴贝虫后,可导致贫血、高热、血红蛋白尿、黄疸、肌痛等症状,临床症状轻重不一,可由无症状感染到威胁生命,主要取决于宿主的身体状况和寄生虫.常用的检查方法有涂片染色法、动物接种分离法、血清学检测法及分子生物学检测法.该文就巴贝虫的形态学特点、生活史、基因组、致病性、临床与实验室诊断以及预防治疗方面做一综述.     

Comparative infectivity of Babesia divergens and a zoonotic Babesia divergens-like parasite in cattle

Babesia divergens-like parasites identified in human babesiosis cases in Missouri and Kentucky and in eastern cottontail rabbits (Sylvilagus floridanus) on Nantucket Island, Massachusetts, share identical small subunit ribosomal RNA gene sequences. This sequence is 99.8% identical to that of Babesia divergens, suggesting that the U.S. parasite may be B. divergens, a causative agent of human and bovine babesiosis in Europe. Holstein-Friesian calves were inoculated with cultured Nantucket Island Babesia sp. (NR831) and B. divergens parasites and monitored by clinical signs, Giemsa-stained blood films, PCR, and culture. The NR831 recipients did not exhibit clinical signs of infection and remained negative for all assays. The B. divergens recipients developed clinical infections and became positive by all assays. NR831 recipients were fully susceptible upon challenge inoculation with B. divergens. This study confirms that the Nantucket Island Babesia sp. is not conspecific with B. divergens based on host specificity for cattle.     

Wild ungulates as Babesia hosts in northern and central Italy

Babesia and Theileria species were investigated in wild ungulates of Northern and Central Italy. Of 355 blood samples examined, 108 (30.4%) were positive to molecular diagnostics (polymerase chain reaction [PCR] with specific primers and sequencing). The sequence analysis showed that the roe deer is a susceptible host for several piroplasms belonging both to Babesia (31%) and Theileria (14.2%) species, whereas fallow deer and wild boar harbor only Theileria species (49% and 2.6%, respectively). Strains related to B. divergens are highly present (28.3%) in the roe deer, which, however, also harbors Babesia MO1 type and Babesia microti-like organisms. Babesia EU1 type is described for the first time in a roe deer in Italy. The finding in roe deer of Babesia species involved in human babesiosis is of concern for public health, mainly because ecological changes in progress cause the increase of both the deer species and the vector tick populations.     

Babesiosis of human and domestic dog; ethiology, pathogenesis, diagnostics

This article presents the current state of our knowledge on babesiosis (piroplasmosis), one of the dangerous, invasive disease of humans and animals, transmitted by ticks. It is included among emerging diseases because its spread and significance have increased in recent years. This sickness is caused by intraerythrocytic parasites belonging to the Babesia species and it is a well-known zoonosis occurring in animals; as a human disease it was unknown almost till the first half of the last century. The intensified migration of human population and human interference in a forest biotope caused that number of recognized cases has grown considerably in recent years. Piroplasmosis in dogs is widely spread all over the world and it is caused by several Babesia species. The principal etiological factor of babesiosis in dogs is B. canis, which turned out to be a collective species represented by three subspecies for which the vectors are three different species of ticks. Their geographical extent indicates the endemic areas for this often fatal disease. A technique, the most often applied in the detection of Babesia is a full blood smear stained with Giemsa or Wright method. However, the estimation of the specimen depends to a large extent on the experience of the diagnostician. The immunological and serological methods are characterized with a high specificity and sensitivity but there are patients in which the false negative results have been obtained. Therefore, the traditional methods have been complemented or even ousted by the molecular methods, in which polymerase chain reaction (PCR) brings the biggest profits. However, the standardization of this technique still remains under elaboration. The usefulness of the PCR protocol has been tested with different molecular destinations from which sequences of genes encoding rRNA for small ribosomal subunit are taken into consideration. Within ribosome, the evolutionally conservative areas can be distinguished, i.e. having the nucleotide sequences similar to the majority or all Babesia species and to others closely related to them. Such construction of gene enables designing of starters complementary to conservative sites to PCR, detecting a large group of related organisms. Another molecular marker allowing on the accurate identification of Babesia is gene encoding the beta-tubuline protein. There are two introns within this gene, from which the first one shows a big variability with regard to the length as well as to the nucleotide sequence, therefore, the PCR products show a diverse length depending on the Babesia species. But these differences are too small for some species and, confirming methods that extend time of diagnostics are essential. The other genes which sequences can be used as molecular aim to the detection of DNA and Babesia species diversification are genes encoding the Heat Shock Proteins HSP 70. However, the gene hsp 70 shows a big conservatism of the nucleotide sequence even between the non related organisms; therefore, this method, based on the amplification of whole genome or its fragments, applies mainly in analysis of molecular phylogenetic.     

Morphologic and clinical observations in human infection with Babesia microti

On admission to the hospital, a splenectomized man was found to have 85% of his erythrocytes parasitized by Babesia microti. His extensive parasitemia allowed for direct study of the morphology and ultrastructure of this organism as it appears in human infection; the need for animal inoculation and rescue techniques was thus eliminated. Positive characteristics (other than the tetrad form) that are diagnostic for babesiosis were identified. By transmission and scanning electron microscopy, parasite-induced changes in the erythrocyte membrane were observed; these alterations may explain the hemolysis seen in babesiosis. Factors that may have allowed the patient to sustain such high-level parasitemia are considered. The experience with this patient confirms that exchange transfusion is a reliable, rapid method for reduction of the parasite load in serious infection with B microti.     

Babesia spp. infections transmitted through blood transfusion

Babesiosis in humans is caused by infection with various species of Babesia (Apicomplexa, Piroplasmida), mainly transmitted by an arthropod vector--Ixodes spp. ticks. This review will focus on blood transfusion as another mode of Babesia transmission, especially in endemic areas, as well as the impact of human babesiosis on transfusion medicine.     

巴贝虫棒状体蛋白的研究进展

巴贝虫是一类专性的细胞内寄生的顶复门原虫,是人和动物的重要病原。这类原虫具有相似的亚细胞结构并能分泌与入侵相关的保守蛋白,尤其是在入侵宿主细胞阶段分泌的棒状体相关蛋白被认为是保护寄生虫入侵和繁殖的关键分子,其在虫体入侵的纳虫空泡形成过程中发挥重要作用。随着基因组学和蛋白质组学技术的不断发展,其相关研究也越来越深入。因此,本文就目前研究较多的牛巴贝虫、羊巴贝虫、吉氏巴贝虫、双芽巴贝虫和东方巴贝虫等棒状体相关蛋白的研究现状进行了综述。     

Babesiosis and blood transfusion: flying under the radar

Infectious agents of disease continue to plague transfusion medicine as an increasing number of pathogens are described that pose a potential blood safety risk. While the recent focus has been on newly emerged agents, several well-established pathogens provide timely reminders that other agents continue to pose threats, but invariably 'fly under the radar', thereby failing to elicit adequate measures to prevent their transmission by blood transfusion. Perhaps foremost among this group of agents are the Babesia spp., which have been known to cause human disease, in the USA, for close to 40 years. B. microti, B. divergens and several Babesia-like agents are responsible for a growing number of human babesiosis infections. Concomitantly, in the USA, there has been a sharp rise in the number of transfusion-transmitted infections of Babesia spp., attributable almost exclusively to B. microti. Despite the obvious public health issues posed by Babesia spp., options for preventing their transmission by blood transfusion remain limited. However, recognition that the Babesia spp. are indeed an ongoing and expanding blood safety threat will probably prove instrumental in the development of viable interventions to limit transmission of these agents.