2007-2008年广州市鼠疫宿主动物及媒介监测结果分析

目的了解广州市鼠疫宿主动物及媒介的种群构成及数量分布情况,为鼠疫防治工作积累基础资料。方法采用夜笼法。对捕获鼠类及捡获蚤类进行鉴定,并计算鼠密度、鼠带（染）蚤率和蚤指数;用鼠疫IHA法检测鼠疫F1抗体。结果捕获鼠形动物1601只,分属2目2科4属7种。其中啮齿目动物1451只,食虫目动物150只,总鼠密度（捕获率）为12.09%,鼠密度（捕获率）为11.50%;在242只鼠形动物中发现染蚤鼠46只,捡获蚤92匹,鼠体表蚤经鉴定为印鼠客蚤、猫栉首蚤、缓慢细蚤、适存病蚤;鼠染蚤率为19.01%,总蚤指数为0.38;黄胸鼠蚤指数为0.63;未查出鼠疫F1抗体。结论褐家鼠仍是广州市主要鼠种。主要蚤种是印鼠客蚤。未发现鼠间鼠疫流行迹象。     

2008-2009年广州市鼠疫宿主动物及媒介监测结果分析

目的了解广州市鼠疫宿主动物及媒介的种群构成及数量分布情况,为鼠疫防治工作积累基础资料。方法采用夜笼法,对捕获鼠类及捡获蚤类进行鉴定,计算鼠密度;计算鼠带（染）蚤率和蚤指数;用鼠疫IHA法检测鼠疫F1抗体。结果捕获鼠形动物1890只,分属2目2科4属7种。其中啮齿目动物1 633只,食虫目动物157只,总鼠密度（捕获率）为11.97%,鼠密度（捕获率）为10.35%;在210只鼠形动物中发现染蚤鼠55只,捡获蚤126匹,鼠体表蚤经鉴定为印鼠客蚤、缓慢细蚤、适存病蚤;鼠染蚤率为26.19%,总蚤指数为0.60;黄胸鼠蚤指数为0.63;未查出鼠疫F1抗体。结论未发现鼠间鼠疫流行迹象,褐家鼠仍是广州市主要鼠种,主要蚤种是印鼠客蚤。     

贵州鼠疫流行地区蚤类调查

为制定鼠疫控制方案 ,需查明鼠疫流行地区的蚤类组成、分布和季节消长。采用夹夜法和笼捕法捕获野外和住宅内鼠类 ,梳检体外寄生蚤 ;用粘蚤纸法调查室内游离蚤。共捕获 7种 (含 1未定种 )蚤 ,隶属于 4科 6属 ,其中印鼠客蚤是当地的优势蚤种 ,占 6 5. 0 0 % ;缓慢细蚤和不等单蚤是当地的常见蚤种 ,分别占 2 0 4 5 %和 14 . 18%。家栖鼠中黄胸鼠主要寄生蚤印鼠客蚤的年均染蚤指数为 0 . 88,褐家鼠主要寄生蚤印鼠客蚤的年均染蚤指数为 1.6 6 ,高峰期均为 6～ 10月 ;锡金小鼠主要寄生蚤印鼠客蚤年均染蚤指数为0. 35 ,高峰期为 6～ 7月。因此印鼠客蚤、缓慢细蚤和不等单蚤是鼠疫控制中的主要防治对象     

广州市2009-2010年鼠疫宿主及其媒介监测结果分析

目的了解广州市鼠疫宿主动物及其媒介的种群构成及数量分布情况,为鼠疫防治工作积累基础资料。方法采用夜笼法捕鼠,对捕获鼠类及捡获蚤类进行鉴定,计算鼠密度;计算鼠带（染）蚤率和蚤指数;用鼠疫IHA法检测鼠疫F1抗体。结果捕获鼠形动物1308只,分属2目2科4属9种。其中啮齿目动物1212只,食虫目动物96只,总鼠密度（捕获率）为10.83%,鼠密度（捕获率）为10.03%;在143只鼠形动物中发现染蚤鼠46只,捡获蚤112匹,鼠体表蚤经鉴定均为印鼠客蚤;鼠染蚤率为32.17%,总蚤指数为0.78;黄胸鼠蚤指数为0.59;未查出鼠疫F1抗体。结论未发现鼠间鼠疫流行迹象;褐家鼠仍是广州市主要鼠种;主要蚤种是印鼠客蚤。     

2007年清新县鼠疫监测情况分析

目的分析清远市鼠疫疫情、人群及媒介宿主动物监测情况，为制定鼠疫防治措施提供科学依据。方法在全市范围开展鼠疫疫情监测，在清新县设立人间和宿主动物间监测点。采集健康人血，捕捉活鼠进行血清学和病原学检验。对鼠密度和传播媒介鼠体蚤指数进行统计分析。结果2007年监测期间无鼠疫疫情和自毙鼠疫情报告；采集206份健康人血清进行鼠疫间接血球凝集试验（IHA-F1抗体）全部阴性；共捕获8种鼠形动物（活体和死体）381只，其中褐家鼠占70．52％，黄胸鼠占11．28％，板齿鼠占8．66％。黄毛鼠占3．41％，施氏屋顶鼠占3．15％：臭鼩鼱占1．57％，小家鼠占1．05％，青毛鼠占0．26％；家栖鼠占84．51％。野栖鼠占15．49％：雌雄鼠性别比例为1．31：1；总鼠密度为10．76％。家栖鼠密度为10．14％，野栖鼠密度为11．33％；家栖鼠鼠体蚤指数为0．21，野栖鼠鼠体蚤指数为0．16。鼠体蚤总指数为0．2，印鼠客蚤指数为0．15，游离蚤总指数为0；采集活鼠血清318份进行鼠疫IHA-F1抗体检测全部阴性；对病变鼠脏器172份压印培养鼠疫杆菌．结果全部阴性。结论清新县主要鼠种是褐家鼠。主要蚤种是印鼠客蚤，暂未发现鼠类和人群的鼠疫感染情况。但仍存在鼠疫疫源地生态环境所具有的条件．应扩大监测范围．加强鼠疫相关宿主动物和传播媒介的监测工作。     

2009年泉州市鼠疫监测分析

目的了解泉州市鼠疫宿主动物的种群构成及数量分布情况,为鼠疫防治工作积累基础资料。方法采用夜笼法捕鼠,并对鼠类及捡获蚤类进行鉴定,计算鼠染蚤率和蚤指数;采用鼠疫RPHA和IHA法等检测鼠疫F1抗体。结果 2009年共捕获鼠形动物2134只,鼠种以褐家鼠和黄胸鼠为主,分别占51.15%和26.66%,两者差异有统计学意义（t=2.783,P=0.019）;总鼠密度5.71%,其中山区和沿海地区鼠密度分别为（4.84%±1.51%）、（6.58%±2.01%）,差异无统计学意义（t=1.197,P=0.297）;鼠体总蚤指数和染蚤率分别为1.16和31.52%;印鼠客蚤指数为1.06,游离蚤指数为0.008,这些指标在山区和沿海地区鼠差异均无统计学意义;鼠疫实验室检测用4种方法均未查出鼠疫F1抗体。结论褐家鼠仍是泉州市主要鼠种,主要蚤种是印鼠客蚤,未发现鼠间鼠疫流行迹象。     

一种新的人工膜养蚤装置及影响养殖质量的若干因素的研究

本文介绍了一种新人工膜养蚤装置的研制、影响印鼠客蚤养殖质量的若干因素及繁殖效果的观察。新装置具有设定、实时测量和数值显示功能。温度值的分辨力为 0 1℃ ,控制精度± 0 3℃。通过在新装置上观察印鼠客蚤经Parafilm膜喂鸡和猪血的繁殖效果表明 :印鼠客蚤的总成长率与传统的小白鼠养殖无显著性差别。采用鸡血离体喂养平均每个雌蚤 1 2天的获茧数比猪血多 1 0 6只与小白鼠养殖近似。采用新装置新方法离体养殖印鼠客蚤 ,每雌每代获茧 1 0 5只 ,可羽化次代成蚤 1 0 0只。日常规操作时间由 1h以上缩短为 2 0min以内 ,经计算喂鸡血每代养殖的实际费用约为猪血的 1 / 1 0 ,小白鼠养殖的 1 2 5。     

印鼠客蚤实验室种群的羽化规律研究

为开展蚤传疾病的传播机制、蚤的生理毒理、杀蚤剂的药物开发等研究提供材料．我们用印鼠客蚤的实验室种群进行蚤的羽化规律研究。该种群用人工饲料饲养幼虫，小白鼠作为供血动物。结果表明，在每1000只蚤的繁殖体系中，供血10天后，子代蚤羽化开始的前4天，雌虫占全部成虫的98．6％；羽化的第9、10天为高峰，雌性的日羽化指数（日羽化率×日雌性比）分别为7．3％和6．7％，第14天以后逐渐下降；羽化开始的第5天后，雄蚤的羽化量逐渐增加，到第14天达到高峰．日羽化指数占全部成蚤的5．9％。成蚤日累计羽化率随时间的变化为“S”型。雌性印鼠客蚤的羽化数量与时间呈负相关。可见，印鼠客蚤的雌性个体比雄性发育快，分别存在不同的羽化高峰，两个高峰重叠，延长成蚤羽化高峰日。关键词印鼠客蚤；实验室种群；羽化规律；性比     

滇西南山地农耕区蚤类物种多样性空间分布特征与鼠疫关系

为调查和分析云南西南部山地农耕区蚤类物种多样性空间分布格局、特征及其与人间鼠疫的关系,本文以云南西南部家鼠鼠疫疫源地中的耿马、临沧、陇川、龙陵、盈江、梁河、腾冲和云龙8县市为调查研究的空间范围,对各县市多个乡镇农耕区进行小型兽类及寄生蚤类的调查取样,所获蚤类数据进行群落组织水平的测定和统计学处理,就当地蚤类物种多样性空间分布格局与人间鼠疫之间的关系进行分析和探讨.结果 显示,(1)共捕获小型兽类2890只,隶属于7科19属35种;共采集宿主寄生蚤类2840只,隶属于6科16属27种.其中,印鼠客蚤(44.26％)和缓慢细蚤(20.39％)为数量上的优势种,偏远古蚤(8.56％)、长形病蚤(7.71％)和泸水栉眼蚤(6.76％)3蚤种数量相对较多,为当地的优势种,而其余的蚤种数量都相对较少;(2)蚤类水平分布和海拔分布的聚类分析结果显示均可聚为3类,它们整体反映了各调查样区或取样地点的地理位置、海拔高度和气候环境条件对农耕区蚤类群落和物种的组成、分布具有重要影响;(3)蚤类的Cody指数(β-多样性)沿海拔梯度的增加呈先逐步降低,后再升高的趋势,Sorenson指数随海拔增高呈先升高后降低的单峰分布格局,它们整体反映了滇西南山地农耕区蚤类群落和物种的组成与区系分布在2000～2500 m较高海拔的区域间发生了较大的变化;(4)蚤类的物种丰富度(γ-多样性)沿海拔梯度带变化规律总体呈现了随海拔升高呈先增高后降低的偏单峰分布格局,最大峰值出现在海拔1500～2000 m间,即在云南3类不同气候温层农耕区中,以中暖层气候农耕区蚤类物种丰富度最高;(5)蚤类的物种多样性指数(α-多样性)以腾冲市最高(1.9178),其他依次为梁河(1.6425)、云龙(1.6391)、陇川(1.5071)、龙陵(1.4948)、盈江(1.4778)、临沧(0.9402),而最低为耿马(0.2753);(6)蚤类的物种多样性、丰富度、均匀度、生态优势度和总蚤指数与人间鼠疫病例构成比之间的相关分析结果显示:物种多样性、均匀度与人间鼠疫均呈显著负相关,而生态优势度与人间鼠疫呈显著正相关;但总蚤指数与物种多样性、均匀度、生态优势度、物种丰富度和病例构成比均不相关.结果 表明,在蚤类物种多样性、均匀度高而生态优势度较低的区域,人间鼠疫发生率较低或未发生鼠疫,反之,人间鼠疫的发生率则较高;(7)优势种印鼠客蚤物种多度及其空间分布特征与人间鼠疫的发生与否和流行强度之间都具有重要关系.结果 表明滇西南家鼠鼠疫疫源地农耕区蚤类物种多样性和优势种印鼠客蚤物种多度的空间分布格局和特征与当地人间鼠疫的发生与否、流行强度都存在重要的关系.     

鼠疫由马达加斯加传入我国的风险评估

评估鼠疫经病媒生物和交通工具由非洲马达加斯加传入我国的风险,并据风险值提出风险管理措施建议。从传染病传播三要素(传染源、传播途径、易感人群),识别鼠疫传入风险的影响因素,构建马达加斯加肺鼠疫传入的风险评估体系;并结合中马贸易往来频率、截获鼠类概率,中马两地黑家鼠及印鼠客蚤分布、疫区分布、地理水文情况及港口物流情况等进行推测,进行定性和半定量传入风险评估;并根据风险值和鼠疫防治策略,提出应采取的风险管理措施。结果表明,在中国为马达加斯加第一大贸易伙伴的前提下,马达加斯加鼠疫传入我国的最可能方式为船舶、货物、集装箱工具;山东、天津至广东西南沿海为鼠疫可能传入地区;半定量风险评估分值为4 096,显示鼠疫由马达加斯加经船舶等传入我国属于中等偏低的风险,能有效控制。根据风险评估结果,对马达加斯加船舶及货物集装箱加大卫生检疫查验力度、做好鼠、蚤及疫区的监测和防治、宣传普及鼠疫相关知识是主动应对此次疫情传入风险的防控方式之一。     

Resurgence of the plague in the Ikongo district of Madagascar in 1998. 2. Reservoirs and vectors implicated

Our survey of mammals and fleas arose as a result of an outbreak of bubonic plague at an usually low altitude in the Ikongo district (Madagascar), while a previous study had found anti-F1 antibodies in an endemic hedgehog. Animals were sampled with live traps in two hamlets (Antanambao-Vohidrotra, 540 m alt. and Ambalagoavy, 265 m alt.) and with pitfall traps in a neighbouring forest (750 m alt.). Rat fleas were collected by brushing the fur and free-living fleas by use of light traps. The introduced shrew Suncus murinus was found only in the village of Ambalagoavy while the black rat (Rattus rattus) was found in all three sites and the only seropositive rat was caught at Antanambao-Vohidrotra. In contrast, among the Tenrecidae (endemic shrews and hedgehogs) found in the forest near the first village, four animals were found seropositive for anti-F1 antibodies. One of them was carrying the endemic flea Paractenopsyllus pauliani, not yet reported as a vector of plague. The endemic vector of plague, Synopsyllus fonquerniei, was found only in the first village of Antanambao-Vohidrotra, and the cosmopolite flea Xenopsylla cheopis only in Ambalagoavy. Although no Yersinia pestis could be isolated and no F1-antigen could be detected in these animals, we found evidence of the recent transmission of plague in Antanambao-Vohidrotra and the nearby forest, but not in Ambalagoavy. These data corroborate with the sylvatic plague cycle hypothesis in Madagascar and its involvement in the outcome of the bubonic plague outbreak in this district.     

Rickettsial infections of fleas collected from small mammals on four islands in Indonesia

Ectoparasites were sampled from small mammals collected in West Java, West Sumatra, North Sulawesi, and East Kalimantan, Indonesia, in 2007-2008 and were screened for evidence of infection from bacteria in the Rickettsaceae family. During eight trap nights at eight sites, 208 fleas were collected from 96 of 507 small mammals trapped from four orders (379 Rodentia; 123 Soricomorpha; two Carnivora; three Scandentia). Two species of fleas were collected: Xenopsylla cheopis (n = 204) and Nosopsyllus spp. (n = 4). Among the 208 fleas collected, 171 X. cheopis were removed from rats (Rattus spp.) and 33 X. cheopis from shrews (Suncus murinus). X. cheopis were pooled and tested for DNA from rickettsial agents Rickettsia typhi, Rickettsia felis, and spotted fever group rickettsiae. R. typhi, the agent of murine typhus, was detected in X. cheopis collected from small mammals in West Java and East Kalimantan. R. felis was detected in X. cheopis collected from small mammals in Manado, North Sulawesi. R. felis and spotted fever group rickettsiae were detected in a pool of X. cheopis collected from an animal in East Kalimantan. Sixteen percent of the X. cheopis pools were found positive for Rickettsia spp.; four (10.8%) R. typhi, one (2.7%) R. felis, and one (2.7%) codetection of R. felis and a spotted fever group rickettsia. These data suggest that rickettsial infections remain a threat to human health across Indonesia.     

茂名市区和电白县鼠类广州管圆线虫感染调查

目的了解茂名市区和电白县鼠类广州管圆线虫感染情况,为该地区广州管圆线虫防治工作提供参考依据。方法在村内和野外采用鼠夹和捕鼠笼等方法捕捉鼠类,在确定种类后,取其心肺组织检查广州管圆线虫成虫。结果共检查鼠148只,阳性15只,鼠广州管圆线虫的总感染率为10.14%。褐家鼠、黄胸鼠和小家鼠的感染率分别为12.87%、4.76%和0。野栖鼠和家栖鼠感染率分别为17.14%（12/70）和3.85%（3/78）。结论茂名市区和电白县鼠类中存在广州管圆线虫的感染,褐家鼠是最主要的终末宿主。同时,野栖鼠的感染率明显高于家栖鼠。     

Early-phase transmission of Yersinia pestis by unblocked Xenopsylla cheopis (Siphonaptera: Pulicidae) is as efficient as transmission by blocked fleas

For almost a century, the oriental rat flea, Xenopsylla cheopis (Rothschild) (Siphonaptera: Pulicidae), was thought to be the most efficient vector of the plague bacterium Yersinia pestis (Yersin). Approximately 2 wk after consuming an infectious bloodmeal, a blockage often forms in the flea's proventriculus, which forces the flea to increase its biting frequency and consequently increases the likelihood of transmission. However, if fleas remain blocked and continue to feed, they usually die within 5 d of blocking, resulting in a short infectious window. Despite observations of X. cheopis transmitting Y. pestis shortly after pathogen acquisition, early-phase transmission (e.g., transmission 1-4 d postinfection [ p.i.]) by unblocked fleas was viewed as anomalous and thought to occur only by mass action. We used an artificial feeding system to infect colony-reared X. cheopis with a fully virulent strain of Y. pestis, and we evaluated transmission efficiency 1- 4 d p.i. We demonstrate 1) that a single infected and unblocked X. cheopis can infect a susceptible host as early as 1 d p.i., 2) the number of fleas per host required for unblocked fleas to drive a plague epizootic by early-phase transmission is within the flea infestation range observed in nature, and 3) early-phase transmission by unblocked fleas in the current study was at least as efficient as transmission by blocked fleas in a previously published study using the same colony of fleas and same bacterial strain. Furthermore, transmission efficiency seemed to remain constant until block formation, resulting in an infectious period considerably longer than previously thought.