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1.
了解2009年缅甸入境健康儿童和云南省口岸地区健康儿童肠道病毒(enterovirus,EV)带毒情况并对埃柯病毒7型(ECHO7)和埃柯病毒13型(ECHO13)的基因特征进行了描述。采集9个边境口岸小于15岁的健康儿童粪便标本271份,进行病毒分离和基因测序定型。271份便标本中共检测到EV30株(带毒率为11.1%),其中脊髓灰质炎病毒(poliovirus,PV)6株(阳性率2.8%),均为疫苗株,未发现脊灰野病毒;检测到非脊灰病毒(NPV)24株(阳性率8.9%)。经VP1区核苷酸序列测定,24株NPV全部为人类肠道病毒B组(HEV-B,6个血清型),其中13株为埃柯病毒7型(echovirus 7,ECHO7,占54.17%),5株为ECHO13(占20.83%)。未分离到HEV-A组,HEV-C组和HEV-D组病毒。2009年缅甸入境健康儿童和云南省口岸地区健康儿童中肠道病毒携带率较高,且均为HEV-B组病毒,其中主要型别为ECHO7和ECHO13,这两种病毒存在基因多样性特点(即存在不同的基因型)。  相似文献   

2.
The epidemiological characteristics of meningococcal infection in Uzbekistan during the period of 8 years since its last epidemic rise in 1972 is presented. Differences in the intensity of the epidemic process among the urban and rural population due to a considerable isolation of most of the rural populated localities from the district centers and the low population density in the republic have been established. The seasonal distribution of the infection had a winter-spring character in urban areas and a spring character in rural areas. 63.4% of all cases were children under 14 years. In cities a high morbidity level among adolescents and young people was determined mainly by visitors from rural areas. A high epidemiological importance of healthy carriers, predominantly schoolchildren and young people was established. The immunological studies of humoral immunity in different groups of the population indicate that the process of immunization was more rapid in cities.  相似文献   

3.
1984年我们对北京地区的乙型脑炎病毒和M14病毒进行了监测,观察到三带喙库蚊季节消长高峰在8月中旬,较发病率较高的1980年和1981年晚3周左右:乙型脑炎病毒检出率(批)为16.1%,最低现场感染率为1:303,检出高峰在8月中旬(44.0%),较1981年晚2周以上;到8月初才发现所感染的猪,明显晚于1980年和1981年,受上述众因素的影响,本年度本市乙型脑炎发病率仍较低(0.8/10万),在M14病毒的监测中,发现三带喙库蚊环病毒M14病毒检出率为9.32%,最低现场感染率为1:526,当年最高检出率(32%)和最低现场感染率高峰(1:156),高峰出现在8月30日,与乙脑病毒自然感染率出现的高蜂相一致;猪感染M14病毒与感染乙脑病毒的时间基本相同,表明这两种病毒在自然界传播中不存在明显的互相干扰关系,乙脑低流行年的出现并未受到M14病毒的影响。  相似文献   

4.
Avian influenza virus (AIV) surveillance studies in wild birds are usually conducted in rural areas and nature reserves. Less is known of avian influenza virus prevalence in wild birds located in densely populated urban areas, while these birds are more likely to be in close contact with humans. Influenza virus prevalence was investigated in 6059 wild birds sampled in cities in the Netherlands between 2006 and 2009, and compared with parallel AIV surveillance data from low urbanized areas in the Netherlands. Viral prevalence varied with the level of urbanization, with highest prevalence in low urbanized areas. Within cities virus was detected in 0.5% of birds, while seroprevalence exceeded 50%. Ring recoveries of urban wild birds sampled for virus detection demonstrated that most birds were sighted within the same city, while few were sighted in other cities or migrated up to 2659 km away from the sample location in the Netherlands. Here we show that urban birds were infected with AIVs and that urban birds were not separated completely from populations of long-distance migrants. The latter suggests that wild birds in cities may play a role in the introduction of AIVs into cities. Thus, urban bird populations should not be excluded as a human-animal interface for influenza viruses.  相似文献   

5.
首次建立了用于脊髓灰质炎快速、分型诊断的血清IgM抗体捕捉法ELISA。检测了52例疑似病人,IgM阳性率为76.9%(40/52),而粪便病毒分离率仅为44.2%(23/52),前者的阳性检出率明显高于后者。做病毒分型诊断结果,与分离病毒中和试验定型的总符合率为92.86%(39/42)。检测601例来自全国各省的脊灰疑似病人血清,其阳性率波动于13%~92.3%,平均为61.1%。阳性率与收集血清的病日相关,发病0~3天收集者,阳性检出率为69.5%,4~25天者为64%,26~54天者为52%,55天以上者则未能检出。本检测方法需时1.5天,简便、敏感、特异,重复性良好,适用于脊灰的早期快速诊断。对其实用性进行了讨论。  相似文献   

6.
The downward migration through soil of seeded poliovirus type 1 and echovirus type 1 and of naturally occurring enteroviruses during infiltration of sewage effluent through rapid-infiltration basins was investigated. After 5 days of flooding, the amount of seeded poliovirus type 1 that had migrated 5 to 10 cm downward through the soil profile was found to be 11% of that remaining at the initial burial depth. The amount of echovirus type 1 determined to have moved an equal distance was at least 100-fold less. Migration of naturally occurring enteroviruses during infiltration of sewage effluent through soil could not be measured with accuracy because of the possibility of virus survival from previous applications of effluent. The rate of inactivation for seeded poliovirus 1 and echovirus 1 buried in the infiltration basins ranged between 0.04 and 0.15 log10 units per day during the time when the basins were flooded. Inactivation of these same seeded virus types and of indigenous enterovirus populations in the infiltration basins during the drying portion of the sewage application cycle ranged between 0.11 and 0.52 log10 units per day. The rate of virus inactivation was dependent upon the rate of soil moisture loss. These results indicate that drying cycles during the land application of wastewater enhance virus inactivation in the soil.  相似文献   

7.
报道了在国内5个大中城市部分非免疫功能不全,也未受过免疫抑制剂治疗人群的尿标本中,用PCR法扩增JC病毒的V-T间序列。结果证实JC病毒在中国也是广为蔓廷的病毒,并且各城市间检出率有明显差异,高者达66%(33/50).低者仅14%(7/50),平均为31%(78/250)。中部和南方城市的检出明显高于北方城市。大城市与中等城市,大城市与大城市郊区的检出率有显著性差异,大城市郊区与中等城市无明显差异,与国外研究结果一致。作为进行性多灶性白质脑病病原,本次在国内的检出率与国外结果相近,希望引起有关学者的关注。  相似文献   

8.
The downward migration through soil of seeded poliovirus type 1 and echovirus type 1 and of naturally occurring enteroviruses during infiltration of sewage effluent through rapid-infiltration basins was investigated. After 5 days of flooding, the amount of seeded poliovirus type 1 that had migrated 5 to 10 cm downward through the soil profile was found to be 11% of that remaining at the initial burial depth. The amount of echovirus type 1 determined to have moved an equal distance was at least 100-fold less. Migration of naturally occurring enteroviruses during infiltration of sewage effluent through soil could not be measured with accuracy because of the possibility of virus survival from previous applications of effluent. The rate of inactivation for seeded poliovirus 1 and echovirus 1 buried in the infiltration basins ranged between 0.04 and 0.15 log10 units per day during the time when the basins were flooded. Inactivation of these same seeded virus types and of indigenous enterovirus populations in the infiltration basins during the drying portion of the sewage application cycle ranged between 0.11 and 0.52 log10 units per day. The rate of virus inactivation was dependent upon the rate of soil moisture loss. These results indicate that drying cycles during the land application of wastewater enhance virus inactivation in the soil.  相似文献   

9.
Many avian species are negatively impacted by urbanization, but other species survive and prosper in urbanized areas. One factor potentially contributing to the success of some species in urban areas is the reduced presence of predators or parasite vectors in urban compared to rural areas. In addition, urban areas may provide increased food and water resources, which can enhance immune capacity to resist infection and the ability to eliminate parasites. We determined patterns of blood parasitism, body condition, and immune cell profiles in urban and rural populations of five adult male songbird species that vary in their relative abundance within urban areas. Urban birds generally exhibited less blood parasitism than rural birds. This difference was particularly evident for the urban-adaptable Abert's towhee Pipilo aberti . In contrast, no difference in haemoparasitism was seen between urban and rural populations of the curve-billed thrasher Toxostoma curvirostre , a less-urban adaptable species. In two closely related species, the curve-billed thrasher and the northern mockingbird Mimus polyglottos , urban birds had a higher leukocyte count and a higher heterophil to lymphocyte ratio, which is often associated with chronic stress or current infection, than rural birds. Urban northern mockingbirds were in better condition than rural counterparts, but no habitat-related differences in condition were detected for other species. Parasitic infection was correlated with body condition in only one species, the canyon towhee Pipilo fuscus . Parasitic infection in most species was correlated with changes in leukocyte abundance and profile. The findings suggest that interspecific differences in parasitic infection cannot be attributed entirely to differences in vector abundance or body condition. Interactions between immune function, parasite infection risk, and resource availability may contribute to determining the relative ability of certain species to adapt to cities.  相似文献   

10.
Rectal swabs, throat swabs, fecal samples, tissues, and sera were collected from 334 adult and infant Kenya baboons (Papio cynocephalus) in captivity at this institution over a 5-year period. A total of 4,893 specimens were collected, resulting in the isolation of 582 viral isolates (11.9%). The month of November yielded the lowest isolation rate, while the month of January produced the highest rate. The most commonly isolated viruses in adults and infants were SV6 and SV23, followed by N125, SV15, and SV17 in that order in adults, and SA7, N125, SV15, V340, and SV17 in that order in infants. Nine serotypes, namely enteroviruses SV19, SV42, SA5, A13, and N203, as well as adenoviruses SV15, SV20, SV31, and SV37, were isolated only from adults. Two adenovirus serotypes, SA7 and V340, were recovered predominantly from infants.  相似文献   

11.
Aims: To study the virological quality of surface water from highly urbanized tropical water catchment areas and to determine predominant enteric viral genotypes in surface water. Methods and Results: A wide range of human pathogenic viruses in urban surface waters was screened by nested PCR assays after concentration by ultrafiltration. Among the 84 water samples collected, at least one virus was detected in 70 (83·3%) of these samples. Noroviruses were determined to be the most prevalent enteric viruses detected in urban surface water samples, followed by astroviruses, enteroviruses, adenoviruses and hepatitis A viruses. The molecular characterization of environmental viral isolates suggested co‐circulation of multiple genotypes of both noroviruses GI and GII, astroviruses and enteroviruses in urban surface waters. Conclusions: Human enteric viruses with great genetic diversity were detected in surface waters, indicating the presence of human origin of faecal contamination in highly urbanized water catchment areas. Significance and Impact of the Study: The present study identifies and characterizes potential viral hazards of source waters for drinking water supply and recreational activities. This will enable scientific decisions to be made regarding the selection and prioritization of human pathogenic viruses to be included in the future risk assessment and treatment evaluation for water and wastewater.  相似文献   

12.
登革Ⅱ型病毒经白纹伊蚊滞育卵的传递   总被引:7,自引:1,他引:6  
采用C6/36细胞培养分离病毒的方法检测感染登革Ⅱ型病毒的白纹伊蚊Aedes albopictus滞育卵孵化的F1代蚊虫感染率,从第一个生殖营养周期子代蚊虫中未分离到病毒,第二与第三生殖营养周期子代蚊虫最低感染率没有显著性差异(χ2=0.01,P>0.0 5),感染子代的批阳性率为9.1%,最低感染率为1∶330;间接免疫荧光检测结果表明感染登革Ⅱ型病毒的白纹伊蚊滞育卵孵化的子代成蚊能通过叮咬将登革病毒传播给敏感乳鼠。这些研究结果表明登革病毒能在媒介滞育卵内存活并传至子代,子代蚊虫能通过叮咬敏感宿主水平传播病毒。  相似文献   

13.
为了建立一种快速诊断呼吸道合胞病毒(RSV)感染的方法,根据RSVN基因的核苷酸序列,设计合成了一对引物,经RT-PCR扩增,可检出RSVRNA该引物不能检测流感病毒、副流感病毒RNA。应用该法可检出疑为RSV感染的婴幼儿鼻咽分泌物中的病毒RNA且比病毒分离法敏感,特异性与免疫荧光法一致。结果表明RT-PCR法具有快速、敏感、特异的优点,可用于RSV感染患儿的临床诊断。  相似文献   

14.
Chlorination of indicator bacteria and viruses in primary sewage effluent   总被引:3,自引:0,他引:3  
Wastewater disinfection is used in many countries for reducing fecal coliform levels in effluents. Disinfection is therefore frequently used to improve recreational bathing waters which do not comply with microbiological standards. It is unknown whether human enteric viruses (which are responsible for waterborne disease) are simultaneously inactivated alongside fecal coliforms. This laboratory study focused on the chlorination of primary treated effluent with three doses (8, 16, and 30 mg/liter) of free chlorine as sodium hypochlorite. Seeding experiments showed that inactivation (>5 log(10) units) of Escherichia coli and Enterococcus faecalis was rapid and complete but that there was poor inactivation (0.2 to 1.0 log(10) unit) of F(+)-specific RNA (FRNA) bacteriophage (MS2) (a potential virus indicator) at all three doses. However, seeded poliovirus was significantly more susceptible (2.8 log(10) units) to inactivation by chlorine than was the FRNA bacteriophage. To ensure that these results were not artifacts of the seeding process, comparisons were made between inactivation rates of laboratory-seeded organisms in sterilized sewage and inactivation rates of organisms occurring naturally in sewage. Multifactorial analysis of variance showed that there was no significant difference (P > 0.05) between the inactivation rates for seeded and naturally occurring FRNA bacteriophage. However, laboratory-grown poliovirus was inactivated much more rapidly than were naturally occurring, indigenous enteroviruses (P < 0.001). This may reflect differences in the way indigenous virus is presented to the disinfectant. Inactivation rates for indigenous enteroviruses were quite similar to those seen for FRNA bacteriophage at lower doses of chlorine. These results have significance for the effectiveness of chlorination as a sewage treatment process, particularly where virus contamination is of concern, and suggest that FRNA bacteriophage would be an appropriate indicator of such viral inactivation under field conditions.  相似文献   

15.
目的分析2009年1月—2011年9月广州白云区儿童多次罹患手足口病的流行病学特征。方法采用描述性流行病学分析方法,对2009年1月—2011年9月白云区社区儿童多次罹患手足口病案例进行流行病学分析。结果 2009年1月—2011年9月,共监测到手足口病个案18665例,其中再次罹患手足口病个案542人,发生率为2.95%,以城中村较为密集的西南部病例居多。多次罹患手足口病按月分布的变化规律与总发病水平相关(r=0.84p,<0.0 001),再患手足口病的时间与初次患病感染病原体型别无关。4岁以下儿童易发,占85.24%;男孩发病是女孩的1.75倍;散居儿童与集体儿童发病的比例为1.70∶1,与初次患病比,托幼机构儿童比例显著上升。病原学检测以其他肠道病毒感染为主。结论儿童多次罹患手足口病存在明显季节、地区、性别年龄差异。病原型别多、分布广泛,可能是儿童再患手足口病发生较频繁的主要原因,应加强儿童监护人健康教育和托幼机构卫生管理。  相似文献   

16.
17.
沈阳地区婴幼儿RSV感染的病原学调查研究   总被引:3,自引:0,他引:3  
查明冬春季沈阳地区婴幼儿RSV感染流行情况.采用APAAP法和IFA法对65例临床诊断为急性病毒性下呼吸道感染的婴幼儿进行了检查.在RSV感染的高发季节由RSV引起婴幼儿的急性下呼吸道感染的阳性率为44.60%(29/65),0~6个月婴幼儿感染率最高,为74.07%(20/27),并有明显的喘息倾向.以上结果表明RSV仍是引起婴幼儿急性下呼吸道感染,特别是肺炎和毛细支气管炎的重要病原体,沈阳地区仍有流行.为防止和控制RSV的流行及为RSV的防治提供了依据.  相似文献   

18.
Human enteroviruses in oysters and their overlying waters.   总被引:12,自引:10,他引:2       下载免费PDF全文
The presence of enteroviruses in oysters and oyster-harvesting waters of the Texas Gulf coast was monitored over a period of 10 months. Viruses were detected in water and oyster samples obtained from areas both open and closed to shellfish harvesting. Viruses were detected periodically in waters that met current bacteriological standards for shellfish harvesting. No significant statistical relationship was demonstrated between virus concentration in oysters and the bacteriological and physiochemical quality of water and shellfish. Viruses in water were, however, moderately correlated with total coliforms in water and oysters and with fecal coliforms in oysters. Total coliforms in water were realted to total coliforms in sediment were related only to total coliforms in sediment. Among the physiochemical characteristics of water, turbidity was related statistically to the organic matter content of water and to fecal coliforms in water. There was a marked effect of rainfall on the bacteriological quality of water. Of a total of 44 water samples, 26 yielded virus in concentrations from 4 to 167 plaque-forming units per 100-gallon (ca. 378.5-liter) sample. Of a total of 40 pools of 10 to 12 oysters each, virus was found in 14 pools at a concentration of 6 to 224 plaque-forming units per 100 g of oyster meat. On five occasions, virus was found in water samples when no virus could be detected in oysters harvested from the same sites. This study indicates that current bacteriological standards for determining the safety of shellfish and shellfish-growing waters do no reflect the occurrence of enteroviruses.  相似文献   

19.
The presence of enteroviruses in oysters and oyster-harvesting waters of the Texas Gulf coast was monitored over a period of 10 months. Viruses were detected in water and oyster samples obtained from areas both open and closed to shellfish harvesting. Viruses were detected periodically in waters that met current bacteriological standards for shellfish harvesting. No significant statistical relationship was demonstrated between virus concentration in oysters and the bacteriological and physiochemical quality of water and shellfish. Viruses in water were, however, moderately correlated with total coliforms in water and oysters and with fecal coliforms in oysters. Total coliforms in water were realted to total coliforms in sediment were related only to total coliforms in sediment. Among the physiochemical characteristics of water, turbidity was related statistically to the organic matter content of water and to fecal coliforms in water. There was a marked effect of rainfall on the bacteriological quality of water. Of a total of 44 water samples, 26 yielded virus in concentrations from 4 to 167 plaque-forming units per 100-gallon (ca. 378.5-liter) sample. Of a total of 40 pools of 10 to 12 oysters each, virus was found in 14 pools at a concentration of 6 to 224 plaque-forming units per 100 g of oyster meat. On five occasions, virus was found in water samples when no virus could be detected in oysters harvested from the same sites. This study indicates that current bacteriological standards for determining the safety of shellfish and shellfish-growing waters do no reflect the occurrence of enteroviruses.  相似文献   

20.
陈立  李玉雨 《病毒学报》1998,14(3):229-233
吉林省延边地区1996年6月发生无菌性脑膜脑炎流行,在全地区216万人口中,发病人数约5 ̄6千人,死亡2人,为历史上所罕见。从病人脑脊液和粪便标本中分离到多株病毒,分离率较高(分别达到52.4% ̄66.7%)。用WHO提供的RIVM肠道病毒组合血清进行中和定型,不能确定型别。RT-PCR结果表明为肠道病毒。病人早期血清特异性IgM抗性阳性率72.0%,证明所分离的病毒为此次无菌性脑膜脑炎暴发流行的  相似文献   

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