关键词： Polio   Vaccination   Demand   Attitudes   Governance  

摘要： Background: Vaccine hesitancy constitutes a major threat to the Global Polio Eradication Initiative (GPEI), and to further expansion of routine immunisation. Understanding hesitancy, leading in some cases to refusal, is vital to the success of GPEI. Re-emergence of circulating wild poliovirus in northern Nigeria in mid-2016, after 24 months polio-free, gives urgency to this. But it is equally important to protect and sustain the global gains available through routine immunisation in a time of rising scepticism and potential rejection of specific vaccines or immunisation more generally. Methods and findings: This study is based on a purposive sampling survey of 1653 households in high and low-performing rural, semiurban and urban areas of three high-risk states of northern Nigeria in 2013-14 (Sokoto, Kano and Bauchi). The survey sought to understand factors at household and community level associated with propensity to refuse polio vaccine. Wealth, female education and knowledge of vaccines were associated with lower propensity to refuse oral polio vaccine (OPV) among rural households. But higher risk of refusal among wealthier, more literate urban household rendered these findings ambiguous. Ethnic and religious identity did not appear to be associated with risk of OPV refusal. Risk of vaccine refusal was highly clustered among households within a small sub-group of sampled settlements. Contrary to expectations, households in these settlements reported higher levels of expectation of government as service provider, but at the same time lesser confidence in the efficacy of their relations with government. Conclusions: Results suggest that strategies to address the micro -political dimension of vaccination expanding community-level engagement, strengthening the role of local government in public health, and enhancing public participation of women - should be effective in reducing non-compliance, as an important set of strategies complementary to conventional didactic/

摘要： In 1988, the World Health Assembly launched the Global Polio Eradication Initiative (GPEI) (1). Among the three wild poliovirus (WPV) serotypes, only type 1 (WPV1) has been detected since 2012. Since 2014, detection of WPV1 has been limited to three countries, with 37 cases in 2016 and 11 cases in 2017 as of September 27. The >99.99% decline worldwide in polio cases since the launch of the GPEI is attributable to the extensive use of the live, attenuated oral poliovirus vaccine (OPV) in mass vaccination campaigns and comprehensive national routine immunization programs. Despite its well-established safety record, OPV use can be associated with rare emergence of genetically divergent vaccine-derived polioviruses (VDPVs) whose genetic drift from the parental OPV strains indicates prolonged replication or circulation (2). VDPVs can also emerge among persons with primary immunodeficiencies (PIDs). Immunodeficiency-associated VDPVs (iVDPVs) can replicate for years in some persons with PIDs. In addition, circulating vaccine-derived polioviruses (cVDPVs) can emerge very rarely among immunologically normal vaccine recipients and their contacts in areas with inadequate OPV coverage and can cause outbreaks of paralytic polio. This report updates previous summaries regarding VDPVs (3). During January 2016-June 2017, new cVDPV outbreaks were identified, including two in the Democratic Republic of the Congo (DRC) (eight cases), and another in Syria (35 cases), whereas the circulation of cVDPV type 2 (cVDPV2) in Nigeria resulted in cVDPV2 detection linked to a previous emergence. The last confirmed case from the 2015-2016 cVDPV type 1 (cVDPV1) outbreak in Laos occurred in January 2016. Fourteen newly identified persons in 10 countries were found to excrete iVDPVs, and three previously reported patients in the United Kingdom and Iran (3) were still excreting type 2 iVDPV (iVDPV2) during the reporting period. Ambiguous VDPVs (aVDPVs), isolates that cannot be classified definitively

关键词： 脊髓灰质炎疫苗株病毒   急性弛缓性麻痹   疫苗相关脊灰病例  

摘要： 目的了解河北省2011-2015年急性弛缓性麻痹(acute flaccid paralysis,AFP)病例中检出脊髓灰质炎(脊灰)疫苗株病毒阳性病例的流行病学特征。方法采用描述性流行病学方法分析河北省2011-2015年报告的AFP病例资料,主要包括病例的流行病学调查资料和采集标本的实验室检测结果。结果从1 889例AFP病例的标本中检出脊灰病毒52株,检出率为2.75%,其中50株为脊灰疫苗相关株病毒,2株为脊灰疫苗高变异脊灰病毒(vaccine high-mutant poliovirus,VHMPV)。病例散在发生,无聚集性;≤3岁儿童病例占82.69%;61.54%的病例脊灰疫苗接种次数≥3次。诊断疫苗相关脊灰病例(vaccine-associated paralytic poliomyelitis,VAPP)11例,首次服苗VAPP发生率为1.86/100万。结论VAPP、疫苗衍生脊灰病毒(vaccine-derived poliovirus,VDPV)引起的麻痹病例及可能造成的VDPV循环(circulating VDPV,c VDPV)必须引起高度重视,保持高质量的监测水平和脊灰疫苗高接种率是非常必要的,可有利于及时发现并科学处置输入的脊灰野病毒疫情以及由脊灰疫苗引起的相关病例,避免造成传播和流行,保障广大儿童的健康。

关键词： 疣/治疗   脊髓灰质炎病毒疫苗   口服/治疗应用  

摘要： 目的探究对扁平疣患者采用脊髓灰质炎减毒活疫苗治疗的临床疗效。方法选取在本门诊进行治疗的扁平疣患者120例作为研究对象,依据随机数字表法将患者分为对照组和观察组,对照组患者采用肌内注射卡介菌多糖核酸液,观察组患者采用口服脊髓灰质炎减毒活疫苗,比较2组患者临床疗效。结果观察组患者总有效率为90.00%,高于对照组患者的65.00%(X^2=4.241,P<0.05)。观察组患者不良反应发生率为23.33%,低于对照组患者的50.00%(X^2=4.243,P<0.05)。结论对患有扁平疣的患者采用脊髓灰质炎减毒活疫苗治疗可缓解患者的临床症状,效果显著,有效提高患者的美观性,值得在临床治疗中广泛应用。

关键词： 脊髓灰质炎病毒   病毒样颗粒   候选疫苗  

摘要： 脊髓灰质炎是一种由脊髓灰质炎病毒引发的高感染性疾病,该病可导致瘫痪甚至致命。口服脊髓灰质炎减毒活疫苗(live attenuated oral poliovirus vaccine,OPV)和脊髓灰质炎灭活疫苗(inactivated poliomyelitis vaccine,IPV)的使用为全球消灭脊髓灰质炎的主要途径,但目前的OPV及IPV均存在生物安全隐患。脊髓灰质炎病毒类病毒颗粒(virus-like particles,VLPs)可保留原病毒的大量重要抗原表位,诱导较强的免疫反应,且无生物安全隐患,是一种具有巨大潜力的疫苗。本文结合全球范围内OPV与IPV的使用情况,对目前脊髓灰质炎病毒VLPs的研究现状及其作为脊髓灰质炎疫苗的意义和目前的困难作一综述。

关键词： AT-risk people   EPIDEMIOLOGY   CAREGIVERS   POLIO -- Prevention   IMMUNIZATION   PSYCHOLOGY of caregivers   DRUGS   ATTITUDES toward health   INTERVIEWING   PATIENT compliance   POLIOMYELITIS vaccine   POLIO vaccination   POLIO transmission   PSYCHOLOGICAL aspects  

摘要： Background Eradication of poliovirus from endemic countries relies on vaccination of children with oral polio vaccine (OPV) many times a year until the age of 5 years. We aimed to determine caregivers' commitment to OPV in districts of Afghanistan at high risk for polio transmission and to examine what knowledge, attitudes, or experiences could threaten commitment. Methods We designed and analysed a poll using face-to-face interviews among caregivers of children under 5 years of age. The sample was drawn via a stratified multistage cluster design with random route household selection. We calculated the percentage of committed and uncommitted caregivers. All percentages were weighted. We then compared percentages of uncommitted caregivers among those with varying knowledge, attitudes, and experiences, using logistic regression to control for possible demographic confounders. Findings Between Dec 19, 2014, and Jan 5, 2015, we interviewed 1980 caregivers, 21% of whom were "uncommitted" to accepting OPV. Multiple measures of knowledge, attitudes, and experiences are associated with lack of commitment. For example, compared with their relevant counterparts, caregivers are more likely to be uncommitted if they did not trust vaccinators "a great deal" (54% vs 9%), if they do not know that polio spreads through contaminated water (41% vs 14%), or if they believe rumours that OPV is not halal (50% vs 21%). Interpretation To enhance OPV commitment, it might be useful to consider a multifactorial approach that highlights building trust in vaccinators, providing facts about transmission, sharing positive messages to overcome key rumours, and strengthening community support for vaccination.

关键词： Human poliovirus receptor (PVR)   CD155   Poliovirus   Immunomodulation  

摘要： The human poliovirus receptor (PVR) is a cell surface protein with a multitude of functions in human biology. PVR was initially identified as the receptor for the human poliovirus and recent discoveries have given a greater insight into both its morphology and its function. Alternative splicing of the PVR gene results in a total of 4 alternatively spliced isoforms. Two of these isoforms lack a complete transmembrane domain and are considered soluble and block viral infection;the remaining two transmembrane isoforms differ only at their extreme C-terminal domains resulting in differential localization in epithelia and polarity of viral infection. In addition to its role as a receptor for the human poliovirus, several native biological functions have also been uncovered. PVR is an important cell adhesion protein and is involved in the transendothelial migration of leukocytes. Through its interactions with CD226 and TIGIT, transmembrane proteins found on leukocytes, PVR is a key regulator of the cell-mediated immune response. As PVR is differentially regulated in a broad spectrum of cancers, it has a strong potential for clinical use as a biomarker. PVR is also a possible target for novel cancer therapies. Utilizing its natural tropism for PVR, a genetically modified form of the live attenuated poliovirus vaccine is currently being tested for its ability to locate and destroy certain tumors. These recent studies emphasize the importance of PVR in human biology and demonstrate its utility beyond being a viral receptor protein.

关键词： poliovirus   genome recoding   packaging signal   specific infectivity  

摘要： Computer design and chemical synthesis generated viable variants of poliovirus type 1 (PV1), whose ORF (6,189 nucleotides) carried up to 1,297 "Max" mutations (excess of overrepresented synonymous codon pairs) or up to 2,104 "SD" mutations (randomly scrambled synonymous codons). "Min" variants (excess of under-represented synonymous codon pairs) are nonviable except for P2(Min), a variant temperature-sensitive at 33 and 39.5 degrees C. Compared with WT PV1, P2(Min) displayed a vastly reduced specific infectivity (si) (WT, 1 PFU/118 particles vs. P2(Min), 1 PFU/35,000 particles), a phenotype that will be discussed broadly. Si of haploid PV presents cellular infectivity of a single genotype. We performed a comprehensive analysis of sequence and structures of the PV genome to determine if evolutionary conserved cis-acting packaging signal(s) were preserved after recoding. We showed that conserved synonymous sites and/or local secondary structures that might play a role in determining packaging specificity do not survive codon pair recoding. This makes it unlikely that numerous "cryptic, sequence-degenerate, dispersed RNA packaging signals mapping along the entire viral genome" [Patel N, et al. (2017) Nat Microbiol 2: 17098] play the critical role in poliovirus packaging specificity. Considering all available evidence, we propose a two-step assembly strategy for +ssRNA viruses: step I, acquisition of packaging specificity, either (a) by specific recognition between capsid protein(s) and replication proteins (poliovirus), or (b) by the high affinity interaction of a single RNA packaging signal (PS) with capsid protein(s) (most +ssRNA viruses so far studied);step II, cocondensation of genome/capsid precursors in which an array of hairpin structures plays a role in virion formation.

关键词： Polio   Vaccination   Oral polio vaccine   Sabin   cVDPV   Cessation  

摘要： The globally synchronized removal of the attenuated Sabin type 2 strain from the oral polio vaccine (OPV) in April 2016 marked a major change in polio vaccination policy. This change will provide a significant reduction in the burden of vaccine-associated paralytic polio (VAPP), but may increase the risk of circulating vaccine-derived poliovirus (cVDPV2) outbreaks during the transition period. This risk can be monitored by tracking the disappearance of Sabin-like type 2 (SL2) using data from the polio surveillance system. We studied SL2 prevalence in 17 countries in Africa and Asia, from 2010 to 2016 using acute flaccid paralysis surveillance data. We modeled the peak and decay of SL2 prevalence following mass vaccination events using a beta-binomial model for the detection rate, and a Ricker function for the temporal dependence. We found type 2 circulated the longest of all serotypes after a vaccination campaign, but that SL2 prevalence returned to baseline levels in approximately 50 days. Post-cessation model predictions identified 19 anomalous SL2 detections outside of model predictions in Afghanistan, India, Nigeria, Pakistan, and western Africa. Our models established benchmarks for the duration of SL2 detection after OPV2 cessation. As predicted, SL2 detection rates have plummeted, except in Nigeria where OPV2 use continued for some time in response to recent cVDPV2 detections. However, the anomalous SL2 detections suggest specific areas that merit enhanced monitoring for signs of cVDPV2 outbreaks. (C) 2017 The Author(s). Published by Elsevier Ltd.

关键词： Circulating vaccine derived poliovirus (cVDPV)   Cross-neutralization   Human immunity   Immune deficiency associated vaccine derived poliovirus (iVDPV)   Monoclonal antibody   Neutralization   Poliovirus   Polio eradication  

摘要： Following the eradication of wild poliovirus (PV), achieving and maintaining a polio-free status will require eliminating potentially pathogenic PV strains derived from the oral attenuated vaccine. For this purpose, a combination of non-cross-resistant drugs, such as small molecules and neutralizing monoclonal antibodies (mAbs), may be ideal. We previously isolated chimpanzee and human mAbs capable of neutralizing multiple PV types (cross-neutralization). Here, we describe three additional human mAbs that neutralize types 1 and 2 PV and one mAb that neutralizes all three types. Most bind conformational epitopes and have unusually long heavy chain complementarity determining 3 domains (HC CDR3). We assessed the ability of the mAbs to neutralize A12 escape mutant PV strains, and found that the neutralizing activities of the mAbs were disrupted by different amino acid substitutions. Competitive binding studies further suggested that the specific mAb:PV interactions that enable cross-neutralization differ among mAbs and serotypes. All of the cloned mAbs bind PV in the vicinity of the "canyon", a circular depression around the 5-fold axis of symmetry through which PV recognizes its cellular receptor. We were unable to generate escape mutants to two of the mAbs, suggesting that their epitopes are important for the PV life cycle. These data indicate that PV cross-neutralization involves binding to highly conserved structures within the canyon that binds to the cellular receptor. These may be facilitated by the long HC CDR3 domains, which may adopt alternative binding configurations. We propose that the human and chimpanzee mAbs described here could have potential as anti-PV therapeutics. (C) 2017 Elsevier Ltd. All rights reserved.