青海省鼠疫自然疫源地主要媒介蚤生态及流行病学意义分析

鼠疫是由鼠疫杆菌引起的一种人畜共患的自然疫源性虫媒传染病,并且通过自然染疫的媒介昆虫蚤的叮咬而传播.目前,青海省存在有2种类型的鼠疫自然疫源地,即青藏高原喜马拉雅旱獭鼠疫自然疫源地和青海田鼠鼠疫自然疫源地,2种类型的疫源地境内自然染疫的蚤类有9种,即斧形盖蚤(Callopsylla dolabris)、谢氏山蚤(Oropsylla silantiewi)、腹窦纤蚤深广亚种(Rhadinopsylla li ventricasa)、人蚤(Pulex irritans)、红羊新蚤(Neopsylla hongyangensis)、圆指额蚤上位亚种(Frotopsylla wagneri superjecta)、原双蚤指名亚种(Amphipsylla primaries primaris)、直缘双蚤指名亚种(Amphipsylla tuta tuta)、细钩盖蚤(Callopsylla sparsilis).     

四川省青海田鼠疫源地地震前后蚤类种群变化

目的 分析地震前后四川省青海田鼠疫源地媒介蚤类种群变化,为做好鼠防工作提供对策.方法 统计、分析四川省2005-2011年期间的鼠疫调查与监测资料.结果 调查发现青海田鼠平均密度191.43 只/ha,地震前后媒介蚤均以细钩盖蚤为主,占67.34％和61.56％,直缘双蚤指名亚种次之,占30.82％和38.12％,青海田鼠寄生蚤染蚤率地震前的9月(54.2％)和地震后的6月(55.24％)较高,而蚤指数以震前的9月(1.00)和震后5月(1.29)较高,染蚤率或蚤指数有一定的季节变化.检验媒介蚤8种、12 922匹,分离鼠疫菌3株,感染鼠疫的媒介蚤为细钩盖蚤.结论 地震前后四川省青海田鼠疫源地蚤类种群有一定变化,地震前后染疫媒介蚤均有细菌分离,说明青海田鼠动物鼠疫持续存在,提示继续加强监测,严防人间鼠疫发生.     

四川省2000-2008年青海田鼠鼠疫疫情监测

目的 分析四川省2000-2008年青海田鼠鼠疫流行趋势.方法 按照"全国鼠疫总体规划"和"四川省鼠疫监测方案"及实施细则进行调查.结果 2000-2008年每个年度均发生青海田鼠鼠疫流行;鼠平均密度312.41只/ha;青海田鼠体染蚤率42.57%.蚤指数0.88.青海田鼠巢蚤指数55.89;发现染疫动物6种,包括青海田鼠、牧犬、沙狐、家猫、藏系绵羊和长尾仓鼠,其中活体青海田鼠检菌率0.32%,自毙青海田鼠检菌率22.99%;血清学阳检率6.70%.发现蚤类4科11属19种,其中染疫媒介3种,蚤类检菌率0.054%,包括细钩盖蚤、直缘双蚤指名亚种和五侧纤蚤邻近亚种.结论 四川省青海田鼠鼠疫呈连续流行态势.     

2000-2013年四川省石渠县鼠疫自然疫源地初探

目的了解四川省青海田鼠鼠疫疫源地流行态势,为做好鼠疫防控工作提供对策依据。方法统计、整理、分析四川省2000-2013年期间的鼠疫调查与监测资料。结果调查发现青海田鼠平均鼠密度242.53只/ha,发现青海田鼠鼠体及巢穴蚤类9种,细钩盖蚤和直缘双蚤指名亚种为主要寄生蚤(93.76%),其他蚤种占6.24%;青海田鼠体蚤指数0.90、染蚤率42.90%,青海田鼠巢穴均染蚤、巢蚤指数51.65;实验室检测各种宿主动物材料14 970份,获鼠疫菌100株,检菌率0.67%;检验媒介蚤2 484组26 984匹,获鼠疫菌11株,检菌率0.44%;证实染疫动物8种、染疫媒介3种;鼠疫间接血凝检测血清3526份,阳性217份,阳性率6.15%,其中青海田鼠血清阳性率5.60%、犬血清阳性率8.40%。结论2000年以来,四川省青海田鼠疫源地每年均有鼠疫细菌检出和鼠疫血清学检测阳性,说明青海田鼠动物鼠疫持续存在,提示要加强防控鼠疫宣传、培训和监测工作,严防鼠疫在人间发生。     

2011-2012年石渠县青海田鼠巢蚤调查分析

目的了解石渠县青海田鼠鼠疫自然疫源地青海田鼠巢蚤构成及其变化,为鼠疫防治提供科学依据。方法于2011-2012年的5~9月期间每月挖取青海田鼠巢6~12个,对巢穴蚤进行分类鉴定。计算巢蚤指数、染蚤率、Shannon多样性指数、Pielou均匀度指数和Simpson优势度指数。结果鉴定蚤3175匹、属3科8种,染蚤率为100%,蚤指数为41.59,多样性指数平均值0.696;均匀度指数平均值0.887;优势度指数平均值0.524。结论石渠县青海田鼠巢穴染蚤率和蚤指数高,巢蚤优势种为细钩盖蚤和直缘双蚤指名亚种,保存和传播鼠疫的潜在风险较高,应加强疫源地鼠疫监测力度和灭鼠灭蚤工作,防止人间鼠疫发生。     

浙江省鼠及主要鼠传疾病综合监测试点研究

目的 探索病媒生物及相关疾病综合监测模式.方法 在浙江省选择2个病媒生物监测点进行现场研究,整合鼠及鼠疫、肾综合征出血热(HFRS)和钩端螺旋体病(钩体病)监测方案,协调机构和人员在市和县两个层面上开展综合监测;鼠类综合监测时间为2009年6、8、10月,采用鼠笼法捕鼠.结果 在浙江省丽水市和龙游县完成鼠密度、季节消长和鼠传疾病综合监测.2009年丽水市报告钩体病3例,发病率为0.13/10万,HFRS 58例,发病率为2.44/10万;龙游县报告钩体病2例,发病率为0.49/10万,HFRS 1例,发病率为0.25/10万.两地区均无鼠疫病例报告.丽水市共捕获鼠类91只,鼠密度为4.17%;龙游县捕获鼠类37只,鼠密度为1.18%.丽水市以黑线姬鼠为主,龙游县以黄胸鼠为主.丽水市对493只鼠进行媒介昆虫监测,染蚤鼠共51只,染蚤率为10.34%.两地区鼠疫病原学及血清学监测结果均为阴性.丽水市HFRS抗原阳性率为10.42%,明显高于龙游县的4.59%.两地阳性鼠种均为黑线姬鼠.龙游县鼠血标本HFRS抗体阳性率为3.70%;丽水市鼠肾培养钩体阴性,龙游县鼠肾钩体阳性率为0.98%;龙游县鸭血钩体抗体阳性率为80%.结论 对鼠群及鼠疫、HFRS和钩体病开展病媒生物综合监测是可行的,建议加强鼠及鼠传疾病综合监测.

Abstract：

Objective To study the integrated monitoring program regarding mouse and plague, hemorrhagic fever of renal syndrome(HFRS)and leptospirosis. Methods Integrated monitoring plan was used. A designated office coordinated 5 departments' actions within the Zhejiang Provincial Center for Disease Control and Prevention(CDC). Cage-trapping method was conducted to monitor the density of mice from June to October, respectively. Results Lishui municipal CDC had finished the integrated monitoring program on mouse and mouse-borne disease while the Longyou CDC had finished the field investigation, using the integrated monitoring program.Specimens were sent to provincial CDC. The integrated monitoring program needed more number of personnel and better coordination. Lishui reported 3 leptospirosis cases and 58 HFRS cases in 2009,with the incidence rates as 0.13 and 2.44 per 100 000, respectively. Longyou reported 2 leptospirosis case and 1 HFRS cases in 2009, with the incidence rates as 0.49 and 0.25 per 100 000, respectively.Lishui and Longyou had no plague case. Lishui caught 91 mice in 2009 and the density was 4.17%.Longyou caught 37 mice in 2009, with the density as 1.18 percent. Most mice caught from Lishui were Apodemus agrarius and the next was Mus musculus. In Longyou the Rattus tanezumi ranked the first, followed by Apodemus agrarius. The positive rate of HFRS antigen in Lishui and Longyou were 10.42% and 4.59% respectively. The positive rate of HFRS antibody in Longyou was 3.70%. The culture positive rate of leptospirosis in mouse renal of Lishui and Longyou were 0 and 0.98%respectively. The culture positive rate of leptospirosis in pig renal, duck renal, frog renal and cattle urine of Longyou was 0. The culture positive rate of leptospirosis in duck blood of Longyou was 80%.Conclusion The integrated monitoring program on mouse and mouse-borne disease seemed to be feasible and could promote the integrated surveillance and control program on mouse and mouse-borne diseases in China.     

SIR模型在一起校园急性出血性结膜炎暴发疫情处理中的应用

应用易感者-感染者-移出者(SIR)模型模拟学校暴发的急性出血性结膜炎,为疫情处理提供参考.采用经典SIR模型构建数学模型,Malthusian指数递减模型估计采取干预措施后的传染率系数(β),通过疫情早期数据确定参数和设置初始值,使用Matlab 7.1软件进行疫情处理效果模拟.结果 显示在无干预措施下,疫情将经历3个阶段:(1)初期(≤5 d)疫情发展较慢,是采取防控措施的最佳时期;(2)快速发展期(6～15 d)采取防控措施效果不甚理想;(3)中后期(≥16 d)90%以上易感者已被感染,采取措施已无较大意义.在有干预措施的情况下,SIR模型模拟结果显示,新发病例数迅速减少,疫情能得到有效控制,该结果与实际疫情发展情况基本相符.SIR模型对模拟校园急性出血性结膜炎暴发疫情具有较好效果.

Abstract：

To simulate intervention measures in controlling an outbreak of acute hemorrhagic conjunctivitis on one school campus by using the Susceptible-Infected-Recovered (SIR) model, to provide evidence for preparedness and response to the epidemic. Classical SIR model was used to model the epidemic. Malthusian exponential decline method was employed to estimate the infective coefficient β for interventions. The initial value of parameters was determined based on empirical data. The modeling was implemented using Matlab 7.1 software. Without interventions, the outbreak was expected to experience three phrases: (1)early stage (the first 5 days) in which the epidemic developed slowly and could be intervened easily; (2) rapid growing stage (6-15 days) in which the number of infected cases increased quickly and the epidemic could not be well controlled;and (3) medium and late stage (16 days and later) in which more than 90% of the susceptible persons were infected but the intervention measures failed to prevent the epidemic. With the implementation of interventions, the epidemic was predicted to be controlled in the early stage, under the SIR model. The simulation based on the SIR model kept an acceptable consistency with the actual development of epidemic after the implementation of intervention measures. The SIR model seemed effective in modeling interventions to the epidemic of acute hemorrhagic conjunctivitis in the schools.     

中国南方四省区流行的HIV-1 CRF01_AE病毒株基因特征研究

Objective To analyze the genetic characteristics of HIV-1 CRF01_AE strains prevailing in. the four provinces of southern China. Methods Plasma samples were collected from the newly diagnosed HIV-1 individuals reported in 2006 in Guangdong, Guangxi, Jiangxi and Hunan province. The gag and env gene fragments were amplified from RNA template extracted from plasma using RT and nested PCR methods. CRF01_AE sequences were analyzed by phylogcnetie methods and characterized by calculating the genetic distance and Entropy analysis. Results Two main epidemic clusters were found to exist in the CRF01 AE strains from 210 HIV-1 CRF01 AE infected individuals collected in the 4 provinces, southern China. It was found that no international reference strain was closely correlated with cluster Ⅰ , which including 123 samples. The strains in cluster Ⅱ, consisting 57 cases of samples, were closely related with the strains identified in Vietnam. Genetic distance analysis of gag and env genes showed that the diversity of cluster Ⅰ was obviously less than that of cluster Ⅱ. Data on nucleotide polymorphism showed that nucleotides compositions of 42 sites in gag and 40 sites in env wer esignificantly different between the two clusters. When compared with cluster Ⅱ , the polymorphism decreased at 61 nucleotide sites but increased at 21 sites in cluster Ⅰ. Conclusion This was the first report describing that two main epidemic clusters were existed in CRF01_AE strains prevailing in the 4 provinces, Southern China. The vires in cluster Ⅰ was the dominant strain in this region, with shorter period of circulation and higher proportion seen in the HIV-infected population, which might belong to CRF01_AE strain with certain features facilitating the spread of the virus. The virus in cluster Ⅱ was highly homology with the CRF01_AE strains from Vietnam, and seemed to have had several events of epidemics in populations in border regions of China and Vietnam.     

四川省石渠县蚤类种群结构研究

目的：研究四川省石渠县青海田鼠鼠疫自然疫源地宿主动物蚤目昆虫的种群结构。方法：主要通过梳检鼠体，挖鼠巢穴，探獭洞干等方法检蚤，然后按形态学分类方法进行分类鉴定到种（亚种）；结果：在该疫源地不同地区，不同自然地理生境中的10种动物，青海田鼠巢穴以及喜玛拉雅旱獭洞干，发现蚤类4种11属19种（亚种），且不同地点，不同生境，不同宿主动物间蚤类分布各异。结论：发现该疫地主要宿主青海田鼠主要寄生蚤为细钩黄鼠蚤和直缘双蚤指名亚种，喜玛拉雅旱獭主要寄生蚤为斧形盖蚤和谢氏山蚤，高原鼠兔主要寄生蚤为五侧纤蚤邻近亚种和哗倍蚤指名亚种，藏仓鼠主要寄生直缘双蚤指名亚种，青海双蚤和细钩黄鼠蚤，沙狐主要寄生蚤为同鬃蚤。     

青海三江源地区小型兽类体外寄生蚤多样性调查

目的了解三江源地区寄生蚤类的栖息环境特征与蚤类群落结构的关系。方法选用铗夜法,辅之以弓捕和枪击。结果本次调查从青海三江源区内不同生境中检获小兽体外寄生蚤954匹,隶4总科6科16属32种。高寒草甸生境中以哗倍蚤指名亚种为主,占45％;高寒沼泽草甸以细钩盖蚤为主,占48．65％;高山草原以斧形盖蚤为主,占28．92％;灌丛以棕形额蚤指名亚种为主,占22．29％;农田居民区主要是棕形额蚤指名亚种,占75％。甘肃鼠兔体外寄生蚤群落的多样性指数（1．90）最高,其优势种为长鬃双蚤,其次是朝鲜姬鼠和甘肃鼢鼠体外寄生蚤群落的多样性指数,分别为1．58和1．51,其他鼠体外寄生蚤多样性指数均较低。结论通过青海三江源区内小型兽类体外寄生蚤生物多样性调查,来监管和保护源头区域物种多样性,为病媒性疾病防制提供参考依据。     

青海省三江源唐古拉地区蚤、蜱、虱调查

目的了解青海省三江源唐古拉地区蚤、蜱、虱种类分布及自然染疫状况。方法结合对该地区鼠疫疫源地的调查和监测工作,对捕获的小型兽类进行体外寄生虫采集,对蚤、蜱、虱标本分类鉴定,将部分标本送实验室做鼠疫细菌学培养。结果发现该地区蚤、蜱、虱有40种（或亚种）,隶属3目8科20属,其中蚤类5科17属36种,蜱类1科1属1种,吸虱2科2属3种（这些标本均保存在青海省地方病预防控制所）。13种喜马拉雅旱獭寄生蚤中自然感染鼠疫的蚤类有3种,即谢氏山蚤、斧形盖蚤、原双蚤指名亚种,亦从喜马拉雅旱獭体外寄生吸虱——古北拟颚虱中分离到鼠疫菌。结论加大该地区媒介昆虫生物学控制研究,为今后鼠疫防治工作服务。     

河北省草原鼢鼠寄生蚤及流行病学意义的研究

目的调查了解河北省草原鼢鼠寄生蚤种类、组成及其染疫情况,及时掌握其在鼠间鼠疫流行时的地位和参与程度,为更好地控制鼠间鼠疫提供科学依据。方法以挖掘法捕获草原鼢鼠,采集其体外寄生蚤进行分类,分离鼠疫菌。结果共发现蚤类3科7属9种;细菌学检验草原鼢鼠111只,蚤细菌培养68组715匹,未分离到鼠疫菌;血清学检验血清88份,未发现鼠疫菌特异抗体。结论凶双蚤为草原鼢鼠的主要寄生蚤,同时携带多种自然染疫的蚤种,有可能参与鼠疫流行。     

珠恩嘎达布其口岸地区鼠蚤本底调查及分析

目的：珠恩嘎达布其口岸是内蒙古东乌珠穆沁旗中蒙边境的口岸，处于布氏田鼠鼠疫自然疫源地范围内，对鼠、蚤情况进行调查，有利于掌握疫情态势。方法：进行现场调查、资料搜集和分析。结果：该地区有鼠类14种、蚤17种。结论：布氏田鼠是主要宿主(90．8％)，长爪沙鼠等鼠类为次要宿主和偶然宿主。蒙古绵羊不能成为鼠疫的传染源。主要媒介是原双蚤、光亮额蚤和近代新蚤，其他蚤种为次要媒介和偶然媒介。     

重庆市万州及涪陵区潜在鼠疫疫源地调查分析

目的了解三峡库区万州及涪陵区段鼠疫主要宿主动物和媒介蚤类的种类构成、数量分布以及宿主动物感染鼠疫菌的情况,判断当地是否存在鼠疫疫源地。方法采用笼捕法,对捕获鼠类及检获蚤类进行鉴定;计算鼠带蚤率和蚤指数;用间接血凝试验检测鼠疫F1抗体。结果 (1)宿主动物调查,万州区捕获鼠形动物170只,密度为3.20%;涪陵区共捕获鼠形动物303只,密度为5.95%。(2)鼠体蚤指数:万州区共梳理出鼠蚤151匹,染蚤率22.94%,蚤指数0.888;涪陵区共梳理出鼠蚤64匹,染蚤率7.59%,蚤指数0.211。(3)地面游离蚤指数:万州区共布放粘蚤纸3000张,捕获地面蚤5匹,蚤指数0.002;涪陵区共布放粘蚤纸3000张,未捕获地面游离蚤。(4)鼠疫血清学检查:对万州及涪陵区捕获的活体鼠形动物全部进行鼠疫血清抗体检测,结果均为阴性。结论万州及涪陵区虽然未曾发生鼠疫,也不是鼠疫疫源地,但从地理景观、宿主动物、媒介昆虫等方面分析,均存在鼠疫疫源地的条件,有发生鼠疫疫情的可能性。     

2007-2009年四川省旱獭鼠疫流行病学监测

目的分析四川省2007-2009年喜马拉雅旱獭鼠疫流行态势,为四川鼠疫防治提供科学依据。方法按照＂全国鼠疫总体规划＂和＂四川省鼠疫监测方案＂及实施细则进行调查。结果2007-2009年调查发现：每个年度均发生喜马拉雅旱獭动物鼠疫流行;发现染疫动物3种,包括喜马拉雅旱獭、牧犬和藏系绵羊;分离鼠疫菌25株,鼠疫间接血凝试验（IHA）阳性血清9份、旱獭血清最高滴度1∶10240,鼠疫反向血凝试验（RIHA）阳性28份、旱獭最高滴度1∶409600;发现蚤类4科10属11种,主要传播媒介为斧形盖蚤和谢氏山蚤。结论喜马拉雅旱獭动物鼠疫呈连续流行态势。     

2005-2006年浙江省东阳市鼠疫宿主动物监测情况分析

目的了解东阳市鼠疫历史疫区宿主动物的种群构成、变迁及数量分布情况,为鼠疫防治工作提供基础资料。方法采用笼夜法。对捕获的鼠类及捡获的蚤类进行鉴定;计算鼠染蚤率和蚤指数;采用间接血球凝集试验（IHA）检测鼠疫F1抗体;“四步”检验法进行鼠疫病原学活体培养。结果捕获鼠类动物1269只,隶属1目2科6属10种。褐家鼠（67．57％）为室内优势种,黑腹绒鼠（71．72％）为野外优势种,室内外鼠密度分别为1．42％和2．42％。在1197只鼠类动物中发现染蚤鼠10只,捡获蚤17匹,鼠体染蚤率0．84％,总蚤指数0．01。采集鼠血清1216份,经IHA检测均呈阴性,病原学活体培养1007份,未发现鼠疫菌。结论褐家鼠和黑腹绒鼠仍是东阳市室内外的主要鼠种,不等单蚤为主要蚤种,染蚤率和总蚤指数低于鼠疫控制标准警戒线,鼠疫F1抗体和病原学检测均呈阴性,目前未发现有鼠间鼠疫流行迹象。     

浙江省历史鼠疫疫区的蚤类种群分布与寄生关系研究

目的研究浙江省历史鼠疫疫区的蚤类种群、分布及其寄生关系。方法在曾发生过鼠疫流行的地区设立监测点，对检获的鼠体蚤进行分类、鉴定和统计分析。结果对19种共61859只鼠形动物进行检蚤，在其中13种鼠形动物体表中检获蚤类21059匹，总染蚤率为12．38％，总蚤指数为0．340，印鼠客蚤指数为0．032。经对21054匹蚤鉴定隶属于4科9属10种（亚种）；其中缓慢细蚤占54．41％，不等单蚤占20．89％，印鼠客蚤占9．50％。缓慢细蚤的寄生宿主有13种，不等单蚤和印鼠客蚤分别有10种和6种；但这3种蚤的主要寄生宿主均为褐家鼠和黄胸鼠，在这2种主要寄生宿主体表检获的印鼠客蚤、缓慢细蚤、不等单蚤分别占所有宿主寄生蚤的95．60％、92．79％和82．31％。结论浙江省的主要鼠体蚤为缓慢细蚤、不等单蚤和印鼠客蚤，这3种蚤的主要寄生宿主是褐家鼠和黄胸鼠，但具有多重性；上述3种主要寄生蚤在浙江省分布范围广，且在数量上占绝对多数；作为家鼠鼠疫疫源地主要传播媒介的印鼠客蚤，不仅存在于家栖鼠类，也存在于野栖鼠类的黄毛鼠和黑线姬鼠中。提示应对主要传播媒介的印鼠客蚤等进行严密的监视，及时掌握其分布和动态变化，为预防和控制鼠疫的发生与流行提供科学依据。