河南省信阳地区不同宿主梨形虫感染研究

发布时间：2018-06-23 08:41

本文选题：蜱 + 梨形虫　；参考：《中国疾病预防控制中心》2014年博士论文

【摘要】：梨形虫是一类经蜱传播的顶复门原虫,广泛分布于热带和亚热带地区,对人畜均有较大危害。梨形虫纲(Piroplasmea)包括巴贝科(Babesiidae)巴贝属(Babesia)和泰勒科(Theileriidae)泰勒属(Theileria)的多种原虫,可引起动物巴贝虫病(Babesiaosis)和泰勒虫病(Theileriosis)。自然状态下,巴贝虫和泰勒虫通过媒介蜱进行生物性传播,故其地理分布与蜱的地理分布密切相关。大多数种类的巴贝虫和泰勒虫只对动物致病,我国家畜中巴贝虫和泰勒虫感染非常普遍,据调查在全国的12个省、自治区均有分布,严重威胁畜牧业发展。有少数巴贝虫,如分歧巴贝虫(B.divergens)和微小巴贝虫(B.microti)对人也有较强的致病性。般认为,泰勒虫对人没有致病性,但是近年有少量研究报道显示某些种类的泰勒虫也可感染人类。人感染这类寄生虫后的临床症状主要表现为发热、血红蛋白尿、溶血性贫血等。蜱是一类专营吸血的体外寄生虫,目前全世界已经发现18个属超过900种,中国目前已发现10个属119种,包括100种硬蜱,10余种软蜱。中国的蜱传疾病在时空上分布不均,其中云南、甘肃、新疆、台湾、福建等省区为中国蜱传疾病的高发地区。由于蜱传疾病的病原体种类很多,同一种病原体又可通过多种媒介蜱传播,加上近些年来不断有新的病原体出现,这都使得蜱传疾病的传播和流行变得更加复杂。近些年来,我国蜱传疾病的病例报道不断增加,如临床诊断错误或治疗不及时很可能导致病人病情迅速恶化甚至死亡。2007年河南省信阳市报道了我国首例蜱叮咬致死事件,患者的主要症状为发热、溶血性贫血等,当时由于病原体不明,造成了对患者诊治的延误。这也使得蜱传疾病成为公众关注的焦点。从2007年到2011年,河南省先后发现了1000例以上的病例,超过98%的报告病例来自于信阳地区。虽然当地不曾有人感染巴贝虫的报道,但是部分患者的临床症状与巴贝虫感染症状非常相似。目前,我国对于巴贝虫病和泰勒虫病的传播媒介以及流行特征的研究相对较少,对这一类新发人畜共患原虫病的研究还不够深入,所以对其潜在流行风险也知之甚少。所以,在信阳市对当地多种宿主开展巴贝虫感染以及泰勒虫感染的调查研究,以了解当地巴贝虫病和泰勒虫病的流行特征,为其预防和控制提供科学依据。本研究首先于2012年4月至12月间,在信阳市辖区内随机抽取10个调查点,开展了当地蜱种群和媒介蜱中梨形虫感染调查。共从各种动物宿主(黄牛,水牛,羊,狗)体表采集到308只蜱,经形态学及分子生物学方法分析鉴定,发现298只蜱为长角血蜱(Haemaphysalis longicornis),10只为微小扇头蜱(Rhipicephalus microplus)。经巢式PCR检测、测序分析以及进化关系分析,在长角血蜱中检测到巴贝虫感染6例,泰勒虫感染10例,同时鉴定出2种泰勒虫(T. buffeli和T. luwenshuni)以及3种巴贝虫(B. gibsoni, B. canis vogeli和B. microti)。在10个调查点中,共发现4个调查点(平桥区,新县,淮滨县和固始县)的媒介蜱中无梨形虫感染,在4个调查点(罗山县,息县,潢川县和商城县)的媒介蜱中检测到巴贝虫感染,在2个调查点(mI河区和光山县)的媒介蜱中检测到泰勒虫感染。研究结果显示长角血蜱为当地的优势蜱种,同时也是梨形虫的高效传播媒介。在完成媒介蜱中梨形虫感染调查的基础上,本研究又于2013年4月至12月间,再次随机抽取5个调查点(平桥区,mI河区,罗山县,息县和商城县)进一步开展了对信阳当地家养动物和野生动物中梨形虫感染情况的调查。共采集各种动物(羊,牛,犬,鸡和刺猬)血液样本共531份。经实验室检测后发现当地动物中巴贝虫感染的总阳性率为0.75%,泰勒虫感染的总阳性率为32.58%。共在3个采样点(商城县,息县,狮河区)的宿主动物(羊和犬)中发现巴贝虫感染,在4个采样点(商城县,平桥区,罗山县,mI河区)的宿主动物(羊和刺猬)中发现泰勒虫感染。同时鉴定出两种巴贝虫(B. microti和B. gibsoni),一种泰勒虫(T. luwenshun)。o研究结果显示吕氏泰勒虫(T. luwenshuni)为当地动物中梨形虫感染的主要种类,进化关系分析提示其与能感染人的泰勒虫的遗传进化关系非常相似。在了解信阳地区动物中梨形虫感染情况后,本研究立即在信阳当地开展了高危人群中梨形虫感染情况调查。2013年6-10月间在商城县,息县和平桥区的调查点所在乡卫生院采集发热门诊病人或近期有蜱叮咬史并伴有发热症状的病人的血液样本共310份。经实验室检测共发现2例巴贝虫感染病例,分别在商城县和罗山县各发现1例,经基因测序方法鉴定出微小巴贝虫(B. microti)感染1例。采用反向线点杂交(RLB)技术,检测信阳地区发现的所有梨形虫感染样本是否存在多种梨形虫的混合感染。结合调查所得各种宿主中梨形虫感染数据以及收集的信阳当地生态地理数据和经济学等数据,采用因素分析和多元Logistic回归分析方法,对信阳当地多种宿主梨形虫感染的影响因素进行分析。RLB实验结果并未发现多种梨形虫的混合感染,结果与巢式PCR实验基本一致。单因素和多因素分析结果显示,植被指数为影响多种宿主梨形虫感染的共同影响因素。综合上述研究结果,本研究发现信阳当地多种宿主中均存在巴贝虫和泰勒虫感染。其中,媒介蜱、动物和高危人群中均检测出微小巴贝虫感染。媒介蜱和动物中均检测到吕氏泰勒虫感染,这些病原体对人和动物的影响还有待进一步研究。
[Abstract]:Pyriform worm is a kind of tick - transmitted apex protozoa, widely distributed in tropical and subtropical regions and has great harm to human and animal. Piroplasmea includes many protozoa of Babeko (Babesiidae) Babena (Babesia) and Telco (Theileriidae) Taylor (Theileria), which can cause the animal BABEI disease (Babesiaosis) and Taylor. Insect disease (Theileriosis). In natural state, the BABEI and Taylor worms are transmitted biologically through the medium ticks, so the geographical distribution is closely related to the geographical distribution of ticks. Most species of BABEI and Taylor are only pathogenic to animals. The infection of bberbeworm and Taylor in domestic animals is very common. According to the survey in 12 provinces and autonomous regions of the country A small number of BABEI worms, such as the B.divergens (B.divergens) and the tiny B.microti (B.microti), have a strong pathogenicity to people. It is believed that the Taylor worm is not pathogenic to humans, but in recent years a small number of studies have shown that some species of Taylor can also infect humans. The main clinical symptoms were fever, hemoglobinuria, hemolytic anemia and so on.
Ticks are an extracorporeal parasite specializing in blood sucking. At present, more than 900 species of 18 genera have been found worldwide. 10 genera and 119 species have been found in China, including 100 species of ticks and more than 10 species of soft ticks. In China, tick borne diseases are uneven in time and space, including Yunnan, Gansu, Xinjiang, Taiwan, Fujian and other provinces, which are the high incidence areas of tick borne diseases in China. Tick borne diseases have many kinds of pathogens, and the same pathogen can be transmitted through a variety of media ticks, coupled with the emergence of new pathogens in recent years, all of which have made the spread and epidemic of tick borne diseases more complicated.
In recent years, the case reports of tick borne diseases have been increasing in our country, such as the clinical diagnosis error or the untimely treatment may lead to the rapid deterioration of the patient's condition and even the death of the tick in the city of Xinyang, Henan province. The first case of the tick bite is reported in the city of Henan province. The main symptoms of the patient are fever, hemolytic anemia and so on. From 2007 to 2011, more than 1000 cases were found in Henan. More than 98% of the reported cases came from the Xinyang region. Although there were no reports of BABEI infection, the clinical symptoms of some of the patients were infected with the BABEI. Symptoms are very similar. At present, there are relatively few studies on the media and epidemic characteristics of BABEI and Taylor's diseases. The study of this kind of new zoonosis is not deep enough, so little is known about the risk of its potential epidemic. So, in Xinyang, a variety of local hosts are infected with BABEI. A survey of Taylor worm infection was conducted to understand the epidemiological characteristics of BABEI worm disease and Taylor worm disease in order to provide scientific evidence for its prevention and control.
In this study, from April 2012 to December, 10 survey sites were randomly selected from Xinyang area to investigate the infection of pyriform insects in local ticks and ticks. A total of 308 ticks were collected from various animal hosts (yellow cattle, buffalo, sheep and dogs), and 298 ticks were found to be long horned blood by morphological and molecular biological methods. Ticks (Haemaphysalis longicornis) and 10 only Rhipicephalus microplus. Through nested PCR detection, sequencing analysis and evolutionary relationship analysis, 6 cases of BABEI infection and 10 cases of Taylor worm infection were detected in chlorpyrifos, and 2 species of Taylor (T. buffeli and T. luwenshuni) and 3 species of BABEI (B. gibsoni, B.) were identified. S vogeli and B. microti). In 10 survey sites, 4 survey sites (Pingqiao, Xinxian County, Huaibin county and Gushi county) were found to have no pyriform infection in the media ticks, and BABEI insect infection was detected at 4 survey points (Luoshan County, Xixian County, Huangchuan county and Shangcheng County), and detected in the media ticks of 2 survey points (mI and Guangshan counties). Taylor worm infection. The results indicate that the blood ticks are the dominant species in the area, and they are also efficient vectors for the production of piriform worms.
On the basis of the investigation of the infection of pyriform insect in the media ticks, this study was conducted from April 2013 to December. 5 survey sites (Pingqiao District, mI river area, Luoshan County, Xixian County and Shangcheng County) were further investigated. The infection of pyriform insects in domestic domestic animals and wild animals in Xinyang was further carried out. A total of 531 blood samples were found in dogs, chickens and hedgehogs. After laboratory tests, the total positive rate of bBeetle infection was 0.75%, and the total positive rate of Taylor infection was found in the host animals (sheep and dogs) of 32.58%. in 3 sampling points (Shangcheng County, Xixian County, Shi River), and 4 sampling points (Shangcheng County, Pingqiao District, Luo). Taylor worm infection was found in the host animals (sheep and hedgehog) of mountain county, mI river area. Two species of BABEI (B. microti and B. gibsoni) were identified. The results of a Taylor (T. luwenshun).O study showed that the Taylor worm (T. luwenshuni) was the main species of pyriform infection in the local animals. Evolutionary relationship analysis suggested that it could infect people. The genetic evolution of the Taylor worm is very similar.
After understanding the infection of pyriform insects in the animals of Xinyang, this study immediately conducted a survey on the infection of pyriform insects in high risk population in Xinyang. In 6-10 months of.2013 in Shangcheng County, Xixian County and Pingqiao District, the township health centers collected fever outpatient or the blood of patients with the history of ticks and fever symptoms in the near future. A total of 310 samples were found. 2 cases of BABEI infection were found in the laboratory. 1 cases were found in Shangcheng County and Luoshan county respectively. 1 cases of small Babe (B. microti) infection were identified by gene sequencing.
Reverse line point hybridization (RLB) was used to detect the presence of a mixed infection of a variety of pear shaped worms in the Xinyang region. The data of the infection of pyriform insects in various hosts and the local eco geographic data and economics collected in Xinyang were analyzed by factor analysis and multiple Logistic regression. Analysis of the factors affecting the infection of pear shaped insects in Xinyang, the results of the.RLB experiment did not find a mixed infection of a variety of pyriform worms. The results were basically consistent with the nested PCR experiment. The results of single factor and multi factor analysis showed that the vegetation index was the common influence factor of the infection of various hosts of the host pear.
In this study, we found that there were BABEI and Taylor in various host hosts in Xinyang. Among them, both media ticks, animals and high risk populations detected the infection of bainiba. Both media ticks and animals detected the infection of Taylor. The effects of these pathogens on humans and animals were still to be further studied.
【学位授予单位】：中国疾病预防控制中心
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R531

【参考文献】