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排序方式: 共有909条查询结果,搜索用时 15 毫秒
41.
《Vaccine》2018,36(19):2529-2544
BackgroundThe success of human papillomavirus (HPV) national immunization program depends on effective strategies in optimizing the uptake of HPV vaccine. Given the increasing number of economic evaluations, this review was conducted to update the economic evidence on HPV vaccination, by focusing on: (i) 9-valent vaccine compared to bi- or quadrivalent vaccine; (ii) gender-neutral vaccination compared to female only vaccination; and (iii) multiple age cohort immunization compared to single age cohort immunization.MethodsSearches were performed until June 2016 using 4 databases: PubMed; Embase; Cochrane Library; and LILACS. The combined WHO, Drummond and CHEERS checklist were used to evaluate the quality of included studies.ResultsThirty-four studies were included in the review and most of them were conducted in high-income countries. The inclusion of adolescent boys in vaccination program was found to be cost-effective if vaccine price and coverage was low. When coverage for female was above 75%, gender-neutral vaccination was less cost-effective than when targeting only girls aged 9–18 years. Current evidence does not show conclusive proof of greater cost-effectiveness of 9-valent vaccine compared to the older HPV vaccines as the price for 9-valent vaccine was still uncertain. Multicohort immunization strategy was cost-effective in the age range 9–14 years but the upper age limit at which vaccination was no longer cost-effective needs to be further investigated. Key influential parameters identified were duration of vaccine protection, vaccine price, coverage, and discounting rates.ConclusionsThese findings are expected to support policy-makers in making recommendations for HPV immunization programs on either switching to the 9-valent vaccine or inclusion of adolescent boys’ vaccination or extending the age of vaccination.  相似文献   
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《Vaccine》2018,36(4):545-552
Parental decision making about childhood vaccinations is complex and multidimensional. There is a perception that the number of parents having concerns regarding childhood vaccinations has been increasing in Canada. The aim of this study was to explore vaccine hesitancy among Canadian parents and to examine factors associated with a parent’s intention to vaccinate his/her child. Informed by the Theory of Planned Behaviour (TPB) this study assesses potential associations between parents’ knowledge, attitudes and beliefs toward vaccination and their intention to vaccinate their child in the future. A national sample of Canadian parents of children aged 24–59 months (N = 2013) was surveyed using an online survey methodology. Half of the surveyed parents strongly intended to have their child vaccinated in the future. Parents’ information needs and searches as well as parents’ trust in different institutions were associated with intention to vaccinate. Parents who reported having frequently looked for vaccine information, who considered that it was their role as parents to question vaccines, or who had previously experienced difficulty accessing vaccination services were less likely to strongly intend to vaccinate their child in the future. Parents who had a high level of trust in doctors and public health were most likely to strongly intend to vaccinate their child. Results of the multivariate analysis showed that positive attitudes (aOR = 8.0; 95% CI: 6.0, 10.4), higher perceived social support (aOR = 3.0; 95% CI: 2.3, 3.93), and higher perceived behavioural control (aOR = 1.8; 95% CI: 1.4, 2.43) were associated with parents’ intention to vaccinate their child. Findings of this study suggest that trust-building interventions that promote pro-vaccine social norms and that address negative attitudes toward vaccination could enhance vaccine acceptance among Canadian parents.  相似文献   
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Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne infectious disease caused by the SFTS virus (SFTSV). SFTS is mainly prevalent in East Asia. It has a mortality rate of up to 30%, and there is no approved treatment against the disease. In this study, we evaluated the effect of loperamide, an antidiarrheal and antihyperalgesic agent, on the propagation of SFTSV in a cell culture system. Methods: SFTSV-infected human cell lines were exposed to loperamide, and viral titers were evaluated. To clarify the mode of action of loperamide, several chemical compounds having shared targets with loperamide were used. Calcium imaging was also performed to understand whether loperamide treatment affected calcium influx. Results: Loperamide inhibited SFTSV propagation in several cell lines. It inhibited SFTSV in the post-entry step and restricted calcium influx into the cell. Furthermore, nifedipine, a calcium channel inhibitor, also blocked post-entry step of SFTSV infection. Conclusions: Loperamide inhibits SFTSV propagation mainly by restraining calcium influx into the cytoplasm. This indicates that loperamide, a Food and Drug Administration (FDA)-approved drug, has the potential for being used as a treatment option against SFTS.  相似文献   
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目的通过对中国2012年脊髓灰质炎(脊灰)实验室网络(Polio Laboratory Network,PLN)监测数据(未包括香港、澳门特别行政区和台湾地区,下同)进行统计分析,评估其运转情况,为中国重新恢复无脊灰状态提供实验室依据。方法分析中国免疫规划监测信息管理系统数据库中,31个省(自治区、直辖市,下同)报告的急性弛缓性麻痹(Acute Flaccid Paralysis,AFP)病例个案调查表和中国疾病预防控制中心(Center for Disease Control and Prevention,CDC)病毒病预防控制所国家脊灰实验室(National Polio Laboratory,NPL)的监测数据库,总结PLN运转中的质量控制,评价PLN的各项运转指标。结果中国2012年PLN共收集了6163例AFP病例的12204份粪便标本,14d内双份粪便标本采集率为92.6%,合格粪便标本采集率为92.1%。按世界卫生组织(World Health Organization,WHO)第4版《脊灰实验室手册》的要求进行病毒分离和鉴定,试验结果28d内及时反馈率为99%。2012年,在116例AFP病例粪便标本中分离到脊灰病毒(Poliovirus,PV),分离率为2.10%(116/5534);在680例AFP病例粪便标本中分离到非脊灰肠道病毒(Non—polio Enterovirus,NPEV),分离率为12.29%(680/5534)。2012年,NPL收到PLN送检的283株PV,对375株单血清型PV采用衣壳蛋白(Capsid Protein)VP1编码区核苷酸序列测定与分析进行型内鉴定(Intratypic Differentiation,ITD),发现7例(共计25株)疫苗衍生(Vaccine—derived)PV(VDPV),其中Ⅰ型2株,Ⅱ型16株,Ⅲ型7株,未发现野生型(Wild Type)PV(WPV)。2012年,NPL收到环境监测送检的314株PV,全部采用VP1编码区核苷酸序列测定与分析进行ITD,在山东省发现1株VDPV。2012年8月,NPL作为WHO西太平洋区脊灰参比实验室接受并以优异的成绩通过了WHO的年度现场认证;2012年10月,NPL以满分的成绩通过了荧光定量聚合酶链反应(Polymerase Chain Reaction,PCR)和VDPV筛查的职能考核;2012年12月,又以满分通过了WHO核苷酸序列测定和分析的第一次职能考核。在中国PLN中,有11个省级CDC脊灰实验室参加并通过了WHO的实验室现场评估认证;22个省级CDC脊灰实验室参加并以满分的成绩通过了荧光定量PCR和VDPV筛查的职能考核。2012年10月9日,WHO通过对中国AFP病例监测质量和结果的评估,宣布中国重新恢复无脊灰状态。结论2012年,PLN运转正常、敏感有效,在AFP病例和环境监测中未发现WPV,为中国恢复无脊灰状态提供了关键的技术支撑作用。  相似文献   
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BackgroundPrisoners and other high-risk patients who show a sustained virological response (SVR) after treatment for hepatitis C virus (HCV) can become reinfected. We aimed to calculate the rate of HCV reinfection in a large cohort of inmates with SVR and to determine factors that predict reinfection.MethodsWe included all inmates treated for hepatitis C in Catalonia (Spain) from January 2002 to December 2016 who achieved SVR and in whom viral load was subsequently determined. The incidence rate was calculated per 100 person-years (100 py) of follow up. Risk factors associated with reinfection were evaluated by bivariate log-rank test and multivariate Cox regression. Hazard ratio (HR) and their 95% confidence intervals (CI) were calculated.Results602 patients were included, with a mean age of 37.9 years: 95% were men, 74.1% had a history of intravenous drug use (IDU) and 28.7% were HIV-infected. Patients were followed for a total of 2154.9 years (average 3.58 ± 3.1 years). 63 (10.5%) had HCV reinfection. 41 (65.1%) presented different genotype/subgenotype, 8 the initial genotype/subgenotype, and in 14 (22.2%) the genotype could not be determined. Of the 21 reinfected patients who were interviewed, 20 (95.2%) reported IDU after antiviral treatment, and 7 (33.3%) during treatment. The overall incidence of reinfection was 2.9 cases per 100 py. All reinfections occurred in patients with IDU history. At multivariate level, HIV infection was associated with reinfection (HR = 3.03; CI:1.82-5.04).ConclusionIn HIV-infected inmates with IDU history, the rate of reinfection of HCV post-SVR is very high. Prisons play a key role in the detection and treatment of infection and reinfection by HCV and in the post-treatment monitoring in these patients, which should be combined with counseling and the optimization of the harm reduction programs. Effective control of these vulnerable groups favours the elimination of the HCV infection.  相似文献   
49.
云南省德宏州2007年和2010年蚊虫及蚊媒病毒调查   总被引:1,自引:1,他引:0       下载免费PDF全文
目的 调查云南省德宏州蚊虫和蚊媒病毒分布特点。方法 2007年和2010年的7月在德宏州5个县市利用诱蚊灯采集蚊虫标本,采用C6/36和BHK-21细胞分离病毒,RT-PCR和序列分析方法鉴定病毒分离物。结果 共采集到6属29种43 634只蚊虫,其中三带喙库蚊构成比高达78.69%,中华按蚊构成比为14.77%,其他蚊种数量较少。从蚊虫中分离到6株病毒,经RT-PCR和进化分析表明,其中3株为基因Ⅰ型流行性乙型脑炎病毒 (JEV),均分离自三带喙库蚊;1株盖塔病毒 (GETV) 分离自三带喙库蚊; 2株淡色库蚊浓核病毒 (CppDNV) 分别分离自三带喙库蚊和迷糊按蚊。结论 三带喙库蚊是德宏州优势蚊种和蚊媒病毒主要传播媒介,当地存在基因Ⅰ型JEV、 GETV和CppDNV的流行,并与以往云南省及我国其他地区的分离株有较近亲缘关系。  相似文献   
50.
Hepatitis B virus (HBV) is a widespread blood-borne pathogen associated with the complication of liver cirrhosis and hepatocellular carcinoma, particularly in south-east Asian and African countries where HBV is highly endemic and the budget and resources are limited. Therefore, simple, rapid, and portable field detection methods are crucial to efficiently control HBV infection. In this study, using heat-treated DNA, we developed two-field applicable detection assays for HBV based on recombinase-aided amplification (RAA). One was an internal controlled duplex RAA assay using a portable real-time fluorescence detection device, another was an instrument-free visual observation assay using lateral flow dipsticks. The entire experimental time was greatly shortened to less than 40 minutes at 39.0°C. The sensitivities, specificities, and clinical performance of both assays were evaluated. Compared with quantitative polymerase chain reaction assay as a reference, our results demonstrated that the two RAA-based assay obtained 97.18% and 95.77% of sensitivity, respectively, and the specificity was 100%, by testing a total of 157 serum samples with HBsAg positive. We conclude that the advantages of rapidity, simplicity, portability, and visualization of proposed two assays make them great potentials in point-of-care testing of HBV infection by untrained people in resource-limited situations.  相似文献   
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