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1.
目的探讨云南家鼠疫源地鼠疫菌在云南鼠疫菌遗传进化上所处的位置,及其种群流行演化规律。方法按照不同地点、时间及分离源随机选取186株家鼠疫源地鼠疫菌,采用差异区段(DFR)、规律成簇的间隔短回文重复序列(CRISPRs)及多位点可变数目串联重复序列分析(MLVA)3种方法进行分子分型分析;以DFR+CRISPRs双重方法聚类分析划分基因簇,以MLVA26对基因簇再次聚类分析划分亚簇。结果 186株家鼠疫源地鼠疫菌中的184株聚为一个簇(家鼠鼠疫簇),其余2株为独立株;近史流行期、复燃流行期和2016年疫情分离株分别处于不同的亚簇,它们之间的位点差异至少有5个;复燃流行期菌株共有5个亚簇和6个独立株,其中2个亚簇为主要的基因亚簇,即滇西亚簇和滇西南-滇东-广西-贵州亚簇,它们之间有4个位点差异。结论家鼠鼠疫菌是云南鼠疫菌中最晚出现的菌株,近史流行期菌株与复燃流行期菌株菌株存在较大差异,而复燃流行期的鼠疫流行是复燃和扩散并存的结果。 相似文献
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目的探讨云南家鼠疫源地鼠疫菌在云南鼠疫菌遗传进化上所处的位置,及其种群流行演化规律。方法按照不同地点、时间及分离源随机选取186株家鼠疫源地鼠疫菌,采用差异区段(DFR)、规律成簇的间隔短回文重复序列(CRISPRs)及多位点可变数目串联重复序列分析(MLVA)3种方法进行分子分型分析;以DFR+CRISPRs双重方法聚类分析划分基因簇,以MLVA26对基因簇再次聚类分析划分亚簇。结果 186株家鼠疫源地鼠疫菌中的184株聚为一个簇(家鼠鼠疫簇),其余2株为独立株;近史流行期、复燃流行期和2016年疫情分离株分别处于不同的亚簇,它们之间的位点差异至少有5个;复燃流行期菌株共有5个亚簇和6个独立株,其中2个亚簇为主要的基因亚簇,即滇西亚簇和滇西南-滇东-广西-贵州亚簇,它们之间有4个位点差异。结论家鼠鼠疫菌是云南鼠疫菌中最晚出现的菌株,近史流行期菌株与复燃流行期菌株菌株存在较大差异,而复燃流行期的鼠疫流行是复燃和扩散并存的结果。 相似文献
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目的探讨云南家鼠疫源地鼠疫菌在云南鼠疫菌遗传进化上所处的位置,及其种群流行演化规律。方法按照不同地点、时间及分离源随机选取186株家鼠疫源地鼠疫菌,采用差异区段(DFR)、规律成簇的间隔短回文重复序列(CRISPRs)及多位点可变数目串联重复序列分析(MLVA)3种方法进行分子分型分析;以DFR+CRISPRs双重方法聚类分析划分基因簇,以MLVA26对基因簇再次聚类分析划分亚簇。结果 186株家鼠疫源地鼠疫菌中的184株聚为一个簇(家鼠鼠疫簇),其余2株为独立株;近史流行期、复燃流行期和2016年疫情分离株分别处于不同的亚簇,它们之间的位点差异至少有5个;复燃流行期菌株共有5个亚簇和6个独立株,其中2个亚簇为主要的基因亚簇,即滇西亚簇和滇西南-滇东-广西-贵州亚簇,它们之间有4个位点差异。结论家鼠鼠疫菌是云南鼠疫菌中最晚出现的菌株,近史流行期菌株与复燃流行期菌株菌株存在较大差异,而复燃流行期的鼠疫流行是复燃和扩散并存的结果。 相似文献
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甘肃省临床分离结核分枝杆菌MLVA分型初步研究 总被引:2,自引:0,他引:2
目的随机选取2005-2007年间甘肃省肺科医院临床分离结核分枝杆菌菌株,通过多位点可变数目串联重复序列(Multiple locus variable numbers of tandemrepeats analysis,MLVA)分型,了解甘肃结核分枝杆菌流行菌株基因型情况。方法选择标化的15个VNTR位点,对临床分离菌株DNA进行检测,DNA指纹图谱使用Bio Numerics4.5软件进行统计分析,得出聚类分析结果。结果 228株结核分枝杆菌被分为4大基因群,7个大基因类型,分别包含13(5.7%)、3(1.3%)、7(3.1%)、1(0.4%)、171(75%)、31(13.6%)、2(0.9%)个株菌;在株水平基因分型上,93(40.8%)株为单菌株基因型;其余菌株基因型分别包含2-10株结核分枝杆菌,共构成132个基因簇。结论甘肃结核分枝杆菌菌株存在丰富的基因多态性,ML-VA方法具有较高的基因分型能力,可以满足结核分枝杆菌株水平DNA分型的需要。甘肃省结核分枝杆菌流行株主要为北京家族基因型菌株。 相似文献
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目的研究新疆结核分枝杆菌可变数目串联重复序列(variable number tandem repeats,VNTR)基因分型,初步了解其基因型多态性状况及主要流行株。方法在新疆维吾尔自治区胸科医院收集一个连续时间段的结核分枝杆菌临床分离菌株,采用多位点可变数目串联重复序列分析(the Multiple Loci VNTR Analysis, MLVA)方法进行基因分型研究。基因聚类分析采用BioNumerics 5.0数据库软件。结果共收集到结核分枝杆菌临床分离菌株175株,运用MLVA 175株菌可分为8个基因群(分别为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ、Ⅷ)119种基因型,其中Ⅰ群所占比例最大,达69.14%,经与Spoligotyping结果综合分析,I群即是北京家族,Ⅱ群为CAS家族。结论新疆结核分枝杆菌临床菌株存在明显的VNTR基因多态性,主要流行菌株为VNTR Ⅰ群(北京基因型),首次发现新疆临床菌株中存在CAS家族。 相似文献
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云南省剑川鼠疫自然疫源地的媒介 总被引:2,自引:0,他引:2
1前言鼠疫是由鼠疫菌一宿主一跳蚤和特定的地理空间等构成的特定的生态系统。跳蚤作为鼠疫菌的一种生存空间,有其特定的生态学和流行病学意义。目前关于跳蚤传播鼠疫的研究大多着眼于流行病学方面,而忽视了它的生态学意义。例如研究中用的是实验动物而不是天然的宿主动物(种间差),或用的是天然的宿主动物,但不是来源于自然疫源地本身(地区差)等,研究的系统性被削弱.限制了结论的现场运用['、']。鉴于此,本文根据已有的研究,从生态格局、生态位理论、媒介效能和系统生态学等方面,以结构与功能统一的原理,对云南省剑川鼠疫自… 相似文献
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目的 建立多位点可变数目串联重复序列分析方法(MLVA),并评价其在布鲁杆菌菌株鉴定及流行病溯源中的价值.方法 使用MLVA方法,对16株羊种菌、22株牛种菌、21株猪种菌和10株犬种菌株进行分析,使用BioNumerics(Version 5.0),对16个位点进行聚类分析,聚类方式用平均连锁聚类法(UPGMA).计算每个位点的差异指数,菌株的基因型通过MLVA2010数据库确定.结果 使用MLVA方法,通过Bruce06、Bruce08、Bruce11、Bruce12、Bruce42、Bruce43、Bruce45、Bruce55共8个位点可以区分布鲁杆菌的种;通过Bruce04、Bruce07、Bruce09、Bruce 16、Bruce30共5个位点可以对菌株进行溯源,确定菌株流行病学相关性.结论 MLVA技术是一种分辨率高且易于在省级疾病防控系统监测实验室使用的标准化分型技术,可以加强布病监测能力. 相似文献
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目的 利用DNA规律聚集簇间隔短回文重复序列(Clustered regularlyinter-spaced short palindromic repeats CRISPR)分型方法,全面探索海西地区分离鼠疫菌株是否存在新的基因型,为鼠疫菌溯源鉴定及流行病学分析提供理论依据。方法 分离培养海西地区1961-2009年间取自鼠疫患者、媒介昆虫及中间宿主的50株鼠疫菌后提取其DNA,利用PCR技术,对鼠疫菌CRISPR分型中的YPa、YPb、YPc 3个位点进行扩增,测定其扩增产物核酸序列并进行分析,将测得CRISPR序列与文献最新报道的CRISPR Dictionary和NCBI数据库进行比对,找出新的CRISPR spacer阵列,基因型别,分析其进化关系,最终确定青海省海西州喜马拉雅旱獭鼠疫自然疫源地鼠疫菌株的CRISPR基因库。结果 50株鼠疫菌在3个CRISPR位点上共有24种spacer,其中YPa位点上有13种、YPb位点8种、YPc位点3种,b51是新发现的spacer。50株鼠疫菌可被分为16个基因型,共归为6大CRISPR类群。Ca35′是该地区主要流行类群;Ca7是... 相似文献
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目的探讨福建省人感染布鲁氏菌分离株主要流行株的种型和分子特征,为制定预防控制策略提供依据。方法将布鲁氏菌分离株转种培养并提取基因组DNA,采用传统生物学鉴定和BCSP31-PCR、AMOS-PCR、MLST及MLVA-16等方法进行布鲁氏菌分离株分子鉴定和分型,通过Bionumerics 6.6软件对其进行聚类分析。结果2018-2019年福建省人感染布鲁氏菌22株分离株分子检测结果与传统分型基本相符,为2个种(羊种和猪种)和2个生物型(羊3型和猪3型),其中羊种布鲁氏菌占多数(95.45%);20株布鲁氏菌分离株MLST基因型为ST8,1株为ST17型,1株为新的ST型:ST99的gap基因与已报道的等位基因型不同,被定义为一个新的等位基因型gap(32)。MLVA-16分型为羊种和猪种2个种群,21株羊种布鲁氏菌分为17种基因型,1株猪种布鲁氏菌分为1种基因型,其中15种基因型为单分离株,3种基因型为共享基因型(共7株,占31.82%)。聚类分析显示福建分离株与内蒙古、辽宁、山东和广东地区存在4种共享基因型,均为羊种布鲁氏菌,其他部分菌株与外省菌株遗传距离较近。结论福建省布鲁氏菌主要流行株为ST8型,且MLVA-16分型显示呈高度基因多样性。MLST/MLVA作为传统生物学鉴定补充技术方法,可用于布鲁氏菌遗传多样性分析和分子流行病学溯源调查,以提高布鲁氏菌病监测能力。 相似文献
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目的研究滇西纵谷齐氏姬鼠、大绒鼠鼠疫疫源地的最佳监测时期。方法应用圆形分布的统计方法对滇西纵谷齐氏姬鼠、大绒鼠鼠疫疫源地16年疫情资料进行分析。结果圆形分布平均角计算和检验假设表明,滇西纵谷齐氏姬鼠、大绒鼠鼠疫疫源地鼠疫存在一定的季节高峰(r=0.4777,α=88.2825.s=69.6456.Z=1379,P<0.001),鼠体蚤检菌阳性75%可信区间分布于1月上旬至6月中旬;鼠体蚤检菌阳性95%可信区间分布在11月中旬至次年7月中旬。结论在滇西纵谷齐氏姬鼠、大绒鼠鼠疫疫源地内.11月中旬至次年7月为最佳监测时期。 相似文献
12.
云南省家、野两型鼠疫菌生化特性及营养需求的比较研究 总被引:1,自引:1,他引:1
目的 探讨云南家、野两型鼠疫菌株问遗传背景的关系.方法 采用固体平皿法,对云南省32株家、野两型鼠疫菌,进行了生化特性及营养需求的研究。结果 ①21株家鼠鼠疫菌株中,16株为典型菌株.3株分别在发酵麦芽糖、甘油时出现了阴性和阳性两种发酵菌落.2株显现与野鼠鼠疫相似的生化特性。其中12株为Pgm^-,8株有Pgm^ 和Pgm^-两种菌落.1株为Pgm,19株对谷氨酸半依赖.2株对谷氨酸不依赖.21株均为苯丙氨酸依赖;②11株野鼠鼠疫菌株中.8株为典型菌株.2株分别在发酵麦芽糖、甘油时出现了阴性和阳性两种发酵菌落,1株发酵麦芽糖阳性。9株为Pgm^-,2株有Pgm^-和Pgm^-两种菌落。3株对谷氨酸半依赖,8株对谷氨酸不依赖.11株均为苯丙氨酸依赖。结论 云南省家、野两型鼠疫菌具有亲缘性.家鼠鼠疫可能是由野鼠鼠疫传入的。 相似文献
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云南鼠疫耶尔森菌基因分型研究 总被引:5,自引:0,他引:5
目的通过对来自云南省鼠疫自然疫源地155株鼠疫菌进行基因分型,了解鼠疫菌的进化规律。方法根据22个差异区段(differentregions,DFR)设计引物,PCR扩增鼠疫菌的每个DFR。结果滇西山地闽广沿海居民区黄胸鼠鼠疫自然疫源地137株鼠疫菌的基因型均为9型。滇西山地齐氏姬鼠大绒鼠鼠疫自然疫源地18株鼠疫菌,有10株菌为7型,8株菌为9型。结论滇西山地齐氏姬鼠大绒鼠鼠疫自然疫源地鼠疫菌的基因型为7型和9型,而滇闽广沿海居民区黄胸鼠鼠疫自然疫源地鼠疫菌的基因型主要为9型。两疫源地鼠疫菌在遗传关系上有亲缘性,后者可能由前者进化而来。 相似文献
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目的通过对青海田鼠鼠疫自然疫源地的鼠疫菌进行生化试验来测定其生化性状,并与喜玛拉雅旱獭鼠疫疫源地鼠疫菌和布氏田鼠鼠疫疫源地鼠疫菌的差异进行比较研究。方法选择鼠李糖、甘油、麦芽糖、阿胶糖、蜜二糖、木胶糖、松三糖、乳糖、水杨素、山梨糖、甘露醇、七叶苷、糊精、蔗糖、半乳糖、纤维二糖、山梨醇、尿素、枸橼酸钠、和硝酸钾等项目进行生化试验。结果青海田鼠型菌株的生化性状,与其毗邻地理位置及生态环境一致,分离自喜玛拉雅旱獭的菌株有较大的差异。而与地理位置和生态环境相差甚远的布氏田鼠菌株其生化性状较接近。结论由此可见鼠疫菌的生化性状与宿主的关系更加密切。 相似文献
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Achtman M Morelli G Zhu P Wirth T Diehl I Kusecek B Vogler AJ Wagner DM Allender CJ Easterday WR Chenal-Francisque V Worsham P Thomson NR Parkhill J Lindler LE Carniel E Keim P 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(51):17837-17842
The association of historical plague pandemics with Yersinia pestis remains controversial, partly because the evolutionary history of this largely monomorphic bacterium was unknown. The microevolution of Y. pestis was therefore investigated by three different multilocus molecular methods, targeting genomewide synonymous SNPs, variation in number of tandem repeats, and insertion of IS100 insertion elements. Eight populations were recognized by the three methods, and we propose an evolutionary tree for these populations, rooted on Yersinia pseudotuberculosis. The tree invokes microevolution over millennia, during which enzootic pestoides isolates evolved. This initial phase was followed by a binary split 6,500 years ago, which led to populations that are more frequently associated with human disease. These populations do not correspond directly to classical biovars that are based on phenotypic properties. Thus, we recommend that henceforth groupings should be based on molecular signatures. The age of Y. pestis inferred here is compatible with the dates of historical pandemic plague. However, it is premature to infer an association between any modern molecular grouping and a particular pandemic wave that occurred before the 20th century. 相似文献
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Stone Age Yersinia pestis genomes shed light on the early evolution,diversity, and ecology of plague
The bacterial pathogen Yersinia pestis gave rise to devastating outbreaks throughout human history, and ancient DNA evidence has shown it afflicted human populations as far back as the Neolithic. Y. pestis genomes recovered from the Eurasian Late Neolithic/Early Bronze Age (LNBA) period have uncovered key evolutionary steps that led to its emergence from a Yersinia pseudotuberculosis-like progenitor; however, the number of reconstructed LNBA genomes are too few to explore its diversity during this critical period of development. Here, we present 17 Y. pestis genomes dating to 5,000 to 2,500 y BP from a wide geographic expanse across Eurasia. This increased dataset enabled us to explore correlations between temporal, geographical, and genetic distance. Our results suggest a nonflea-adapted and potentially extinct single lineage that persisted over millennia without significant parallel diversification, accompanied by rapid dispersal across continents throughout this period, a trend not observed in other pathogens for which ancient genomes are available. A stepwise pattern of gene loss provides further clues on its early evolution and potential adaptation. We also discover the presence of the flea-adapted form of Y. pestis in Bronze Age Iberia, previously only identified in in the Caucasus and the Volga regions, suggesting a much wider geographic spread of this form of Y. pestis. Together, these data reveal the dynamic nature of plague’s formative years in terms of its early evolution and ecology.The earliest known cases of human infection with the plague pathogen, Yersinia pestis, date to around 5,000 y ago (1–4). Analyses of ancient Y. pestis genomes from this period suggest that the time window between 6,000 and 4,000 y ago was critical and formative for the evolution and ecology of Y. pestis as we know it today. Four ancient Y. pestis lineages have been identified so far, which can be genomically distinguished based on their adaptations to the flea, the main vector of modern plague. Today, fleas are known to play a central role in the transmission of plague within rodent populations, which can act as reservoirs from where spillovers to human populations typically occur (5, 6). The transmission of Y. pestis by the flea is either facilitated by a blockage of the foregut (proventriculus), where the bacterium produces a biofilm (7), or in a biofilm-independent manner, also known as early-phase transmission (8, 9). The oldest lineages of Y. pestis (2, 4) (hereafter referred to as preLNBA−), and the Late Neolithic and Early Bronze Age (LNBA−) lineage (1, 3) present a genetic background that has been interpreted as being incompatible with flea transmission via the blockage of the foregut (indicated in the naming by the minus sign). While a recently identified ancient lineage also dating to the Bronze Age presents all the genetic adaptations for this highly efficient form of flea transmission (10) (LNBA+; the plus sign indicates the adaptation to the flea vector). Intriguingly, both variants coexisted for millenia and they might have occupied different niches. However, it remains unclear how the different forms of Y. pestis infected humans during prehistory and how the resulting diseases manifested in the human population. Whether plague ecology and transmission as we know it today can serve as a model to understand its manifestation in the past remains also unknown.Elucidating the ecology and transmission will be crucial for understanding how the LNBA+/− lineages of plague, which were widespread across Eurasia for thousands of years (1, 3, 10, 11), have impacted human societies, and how changes in human subsistence and economy have shaped the early evolution of this pathogen. It is currently unknown whether and which types of animal populations served as potential reservoirs of the disease and their identification will be essential for characterizing past Y. pestis transmission dynamics. The absence of an adaptation to the flea vector in some plague lineages suggests that the transmission dynamics were complex. Today, the flea-mediated model is not the only documented form of plague transmission: pneumonic plague can be acquired via respiratory droplets from close human-to-human contact. However, only a few reported outbreaks have been attributed to this transmission mode and usually in contexts of poor ventilation and direct contact with infected individuals (12–17). Additionally, plague has been documented in humans who handled or ingested parts of infected animals (18–22).Changes in human behavior may also have contributed to a higher risk of plague infection. During the LNBA period, archeological evidence attests to technological advances, such as the spread of oxen-drawn carts and wagons (23) and horse domestication (24), which enabled increased human mobility and exploitation of new habitats, such as the Eurasian steppe belt. This ultimately led to the establishment of long-distance networks, in which raw materials such as copper were circulated (25, 26). However, periods of unrest and war could also have played a role in the extended human mobility during the LNBA period. While earlier studies hypothesized that increased mobility was the cause for an early spread of Y. pestis across Eurasia (1, 3), it could also have been its effect. It is also during this period that animal husbandry and mobile pastoralism intensified in the steppe (27), thus facilitating the overlap of ecological niches for zoonoses to occur. The aforementioned changes could have played a role in the likelihood of transmission to humans and the long-distance spread of plague during its early evolution.Here we expand the number of Y. pestis genomes from the LNBA period to offer a higher genomic resolution for important stages in the evolution of the bacterium, as well as its diversity and geographical distribution in the past. By linking the genomic evidence with the available archeological context, we discuss potential transmission mechanisms of plague during its early evolution. 相似文献
17.
Plague had been wreaking havoc in the west ofYunnan including Jianchuan County for long.“Greatdying” was recorded in history of Nazhao Kingdom inancient Yunnan as early as 110 8AD.There weremany different points of view on the origin of plaguein Yunnan among Chinese and foreign scholars.Some believed the disease come from Tibet,andsome believed it come from Burma.After 195 6,hu-man case could not found again,plague epizootic alsodisappeared in the whole province,even thoughplague survei… 相似文献
18.
目的 调查梁河县家鼠鼠疫疫源地宿主动物中是否携带鼠疫噬菌体,并探讨其流行病学意义。方法 2017年采集梁河家鼠鼠疫疫源地4个曾流行过鼠疫乡镇的鼠类标本,以鼠疫疫苗株EV76为饲养菌,采用双层平板法分离鼠疫噬菌体,同时挑取部分噬菌体进行电镜扫描。结果 共获得338份标本(黄胸鼠234只,臭鼩鼱43只,其余61只),分离到29株鼠疫噬菌体,总分离率为8.58%(29/338),其中19株分离自黄胸鼠,分离率为8.12%(19/234),8株分离自臭鼩鼱,分离率为18.6%(8/43);4个乡镇全部有分离到鼠疫噬菌体,其中遮岛镇分离率最高为16.13%(5/31);初次分离这些鼠疫噬菌体时,其噬斑在双层平板上表现为大(直径≥2.0 mm)、中(≥1.0 mm,≤2.0 mm)及小(≤1.0 mm)3种噬斑;2株有代表性噬菌体皆为肌尾病毒科噬菌体。结论 梁河家鼠鼠疫疫源地中普遍存在鼠疫噬菌体,黄胸鼠是主要的携带宿主,所分鼠疫噬菌体为肌尾病毒科噬菌体且具有多态性,值得进一步研究。 相似文献
19.
目的研究青海省鼠疫耶尔森菌(鼠疫菌)基因型分布特征。方法对分离到的青海省148株鼠疫菌,根据已经证实的22个差异区段设计引物,每株鼠疫菌的每个基因差异区段都采用PCR技术进行验证。结果148株青海省鼠疫菌共包括8个基因型,即1、5、7、8、14型、新基因组型和Ype-ancestor型,其中以5型和8型为主。祁连山南麓和青海湖环湖地区的祁连、门源、刚察、海晏、共和、天峻等的菌株绝大多数属于基因型8型,占40.5%(60/148);位于青南高原的格尔木、玉树、扎多、治多、称多、囊谦和曲麻莱等的菌株,其基因型主要为5型,占31.8%(47/148)。青藏高原青海田鼠鼠疫疫源地鼠疫菌基因型全部为14型,占8.1%(12/148)。结论在青海省分离的鼠疫菌中,喜马托雅旱獭鼠疫疫源地鼠疫菌的基因型以5型和8型为主,青海田鼠疫源地鼠疫菌以基因型14型为主。 相似文献
20.
1974年剑川鼠疫自然疫源地的发现,结束了中外学者对云南省是否存在鼠疫自然疫源地的长期争论,这在鼠疫研究史上是一次重大的突破.然而,由于该疫源地位于生物多样性较高、生物地理景观十分复杂的横断山中部,从一开始,在对宿主和媒介的判定、疫源地的结构以及与家鼠鼠疫的关系研究中,在理论与方法上提出了许多新的问题.本文根据结构与功能统一的原理,运用广义信息概念,系统地研究和阐明了该疫源地的鼠疫基本生态格局是以高山姬鼠+褐家鼠:棕形额蚤+特新蚤+人蚤+方叶栉眼蚤群落为贮存子系统;大绒鼠:方叶栉眼蚤+特新蚤群落为流行子系统;松鼠鼠蚤为更替子系统.各子系统的关系是非线性的.指出自该疫源地发现以来没有明确人间病例是由该疫源地的鼠疫生态的系统性决定的,但如果系统进入混沌状态,发生人间鼠疫的可能性依然存在.同时指出虽然很多研究以实验的方法用量化的指标分析鼠疫的系统性,然而由于没有运用系统的概念,结果常常是直接、离散和互相矛盾的对表象的描述,而不是对各要素相互作用的分析和综合,从而颠倒了鼠疫的基本生态学概念. 相似文献