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When the Global Polio Eradication Initiative began in 1988, wild poliovirus (WPV) transmission was reported in 125 countries. Since 2017, Afghanistan and Pakistan remain the only countries with uninterrupted endemic WPV type 1 (WPV1) transmission. This report describes activities and progress toward polio eradication in Afghanistan during January 2022-June 2023. Two WPV1 cases were reported during January-December 2022 and five during January-June 2023 (as of August 26), all from three provinces in the southeast and east regions bordering Pakistan. All five 2023 patients had reportedly received =16 oral poliovirus vaccine doses. WPV1 was detected in sewage samples from a site in the south region in May 2023 and one in the north region in June 2023, the first detections since February 2021 and March 2020, respectively. Restrictions on house-to-house vaccination limit the effectiveness of vaccination campaigns in parts of the south and northeast regions. Because of population movement, the risk for transmission in Afghanistan and Pakistan will remain if WPV1 circulation continues in either country. Despite operational improvements in vaccination activities, interruption of WPV1 transmission in Afghanistan will require committed, uninterrupted efforts, including ongoing coordination with Pakistan on polio eradication activities, to address vaccination coverage gaps that sustain WPV1 circulation. [ABSTRACT FROM AUTHOR]

Post-polio syndrome (PPS) is a rare neurological disorder that affects 20-40% of paralytic and non-paralytic polio survivors. It is estimated that about 15 million people worldwide are survivors of the polio infection that occurred during the 1940s and 1950s, until the vaccine was first introduced. Its main characteristic is the appearance of de novo muscle weakness or its increase and atrophy, accompanied by other symptoms such as fatigue, joint, bone or muscle pain, intolerance to cold, and bulbar symptoms (involvement of swallowing, speech and breathing). PPS usually affects performance in daily activities with a negative effect on patients' quality of life. We present two cases with a diagnosis of PPS, with a current review of the literature. [ABSTRACT FROM AUTHOR]

Since the Global Polio Eradication Initiative (GPEI) was established in 1988, the number of reported poliomyelitis cases worldwide has declined by approximately 99.99%. By the end of 2021, wild poliovirus (WPV) remained endemic in only two countries (Pakistan and Afghanistan). However, a WPV type 1 (WPV1) case with paralysis onset in 2021, was reported by Malawi a year after the World Health Organization (WHO) African Region (AFR) was certified as WPV-free and circulating vaccine-derived poliovirus (cVDPV) cases were reported from 31 countries during 2020-2021 (1,2). cVDPVs are oral poliovirus vaccine-derived viruses that can emerge after prolonged circulation in populations with low immunity and cause paralysis. The primary means of detecting poliovirus transmission is through surveillance for acute flaccid paralysis (AFP) among persons aged <15 years, with confirmation through stool specimen testing by WHO-accredited laboratories, supplemented by systematic sampling of sewage and testing for the presence of poliovirus (environmental surveillance). The COVID-19 pandemic caused disruptions in polio vaccination and surveillance activities across WHO regions in 2020; during January-September 2020, the number of reported cases of AFP declined and the interval between stool collection and receipt by laboratories increased compared with the same period in 2019 (3). This report summarizes surveillance performance indicators for 2020 and 2021 in 43 priority countries* and updates previous reports (4). In 2021, a total of 32 (74%) priority countries† met two key surveillance performance indicator targets nationally, an improvement from 2020 when only 23 (53%) met both targets; however, substantial national and subnational gaps persist. High-performing poliovirus surveillance is critical to tracking poliovirus transmission. Frequent monitoring of surveillance indicators could help identify gaps, guide improvements, and enhance the overall sensitivity and timelines of poliovirus detection to successfully achieve polio eradication. [ABSTRACT FROM AUTHOR]

Background World Health Organization African region is wild poliovirus-free; however, outbreaks of vaccine-derived poliovirus type 2 (VDPV2) continue to expand across the continent including in Chad. We conducted a serological survey of polio antibodies in polio high-risk areas of Chad to assess population immunity against poliovirus and estimate the risk of future outbreaks. Methods This was a community-based, cross-sectional survey carried out in September 2019. Children between 12 and 59 months were randomly selected using GIS enumeration of structures. Informed consent, demographic and anthropometric data, vaccination history, and blood spots were collected. Seropositivity against all 3 poliovirus serotypes was assessed using a microneutralization assay at Centers for Disease Control and Prevention, Atlanta, GA, USA. Results Analyzable data were obtained from 236 out of 285 (82.8%) enrolled children. Seroprevalence of polio antibodies for serotypes 1, 2, and 3 was 214/236 (90.7%); 145/236 (61.4%); and 196/236 (86.2%), respectively. For serotype 2, the seroprevalence significantly increased with age (P =.004); chronic malnutrition was a significant risk factor for being type 2-seronegative. Interpretation Poliovirus type 2 seroprevalence in young children was considered insufficient to protect against the spread of paralytic diseases caused by VDPV2. Indeed, VDPV2 outbreaks were reported from Chad in 2019 and 2020. High-quality immunization response to these outbreaks is needed to prevent further spread. [ABSTRACT FROM AUTHOR]

Despite increased efforts and spending toward polio eradication, it has yet to be eliminated worldwide. We aimed to project economic costs of polio eradication compared to permanent control. We used historical Financial Resource Requirements from the Global Polio Eradication Initiative, as well as vaccination and population data from publicly available sources, to project costs for routine immunization, immunization campaigns, surveillance and laboratory resources, technical assistance, social mobilization, treatment, and overhead. We found that cumulative spending for a control strategy would exceed that for an eradication strategy in 2032 (range, 2027-2051). Eradication of polio would likely be cost-saving compared to permanent control. [ABSTRACT FROM AUTHOR]

The world was never so close to reach the polio eradication: only 37 cases notified in 2016 in only three countries, but the game is not yet at the end. The risk of polio outbreaks in the EU is smaller than it has ever been in the past, but it is not so small that we can ignore it. The EU MS must remain alert and plan and prepare for managing polio events or outbreaks because of the possible dire consequences. The IPV only vaccination schedule universally applied in EU has achieved satisfactory coverage, but constantly leaving small accumulating pockets of susceptible individuals. Moreover the IPV only schedule is not an absolute barrier against poliovirus silent transmission as demonstrated in the recent Israel outbreak. The availability of annually revised S.O.P. from WHO GPEI on the identification and response of a polio event, without local poliovirus transmission or a polio outbreak with sustained transmission, helps and challenge EU countries to update their polio national preparedness plans. The EU/EEA area, in fact, is a peculiar area regarding the polio risk both for its vaccination policy, the large polio vaccines manufactures and the constant immigration from areas at polio high risk, but also EU include cultural and financial potentials crucial to sustain the polio end game strategy and reach the benefit of a world without polio risk. Poliovirus eradication will continue to be challenged as long as there is the worldwide presence of polioviruses in laboratories and vaccine production plants. Most of the world’s OPV vaccines are produced in the EU and many laboratories and research centers store and handle polio viruses. EU Member States are engaged actively in implementing the poliovirus biocontainment plans that are part of the polio eradication strategy and to certify the destruction of poliovirus strains and potentially contaminated biological materials. [ABSTRACT FROM AUTHOR]

Background Using a survey conducted during the 2013–2014 polio outbreak in Somalia, this study examines attitudinal and knowledge-based threats to oral polio vaccine acceptance and commitment. Findings address a key gap, as most prior research focuses on endemic settings. Methods Between November 19 and December 21, 2013, we conducted interviews among 2003 caregivers of children under 5 years in select districts at high risk for polio transmission. Within each district, sample was drawn via a multi-stage cluster design with random route household selection. We calculated the percentage of caregivers who could not confirm recent vaccination and those uncommitted to future vaccination. We compared these percentages among caregivers with varying knowledge and attitudes, focusing on variables identified as threats in endemic settings, using controlled and uncontrolled comparisons. We also examined absolute levels of threat variables. Results Only 10% of caregivers could not confirm recent vaccination, but 32% were uncommitted to future vaccination. Being unvaccinated or uncommitted were related to multiple threat variables. For example, compared with relevant counterparts, caregivers were more likely to be unconfirmed and uncommitted if they did not trust vaccinators “a great deal” (unconfirmed: 9% vs. 2%; uncommitted: 49% vs. 28%), which is also true in endemic settings. Unlike endemic settings, symptom knowledge was related to commitment while rumor awareness was low and unrelated to past acceptance or commitment. Levels of trust and perceptions of OPV effectiveness were high, though perceptions of community support and awareness of logistics were lower. Conclusions As in endemic settings, outbreak responses will benefit from communications strategies focused on enhancing trust in vaccinators, institutions and the vaccine, alongside making community support visible. Disease facts may help motivate acceptance, and enhanced logistics information may help facilitate caregiver availability at the door. Quelling rumors early may be important to prevent them from becoming threats. [ABSTRACT FROM AUTHOR]

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.Funding: Harvard T H Chan School of Public Health and UNICEF. [ABSTRACT FROM AUTHOR]

Background: Since the introduction of polio vaccines in the 1950’s and 60’s, eradication of poliovirus from the world has been technically feasible. Progress towards this goal, however, has been uneven and influenced by social and political factors that challenge the implementation of robust immunization programs. While violence and insecurity are often cited as barriers to eradication, current global risk models are largely based on virologic and immunologic indicators measured at national levels. In this manuscript, we quantify the relevance of indicators of violence and insecurity on the risk of polio spread. Methods and findings: Using logistic regression models and public data sources, we evaluate the relationship between measures of violence and instability and the location of poliomyelitis cases between 2006 and 2015 at the country-level, both individually and after controlling for more proximal determinants of disease, such as nearby circulating poliovirus and vaccination rates. We found that increases in a country’s Fragile States Index (FSI) and Global Peace Index (GPI), aggregate indicators of violence and instability, were associated with the occurrence of poliovirus cases in the subsequent year (p< 0.01), even after controlling for established risk factors. These effects of violence and insecurity must be mediated through immunity and exposure to poliovirus, coarse measures of which are included in our model. This also implies that in our study, and in risk models in general, the interpretation depends on the quality and granularity of available data. Conclusion: National virologic and immunologic indicators understate the risk of poliovirus spread in areas with violence and insecurity, and the inclusion of such factors improves precision. In addition, the link between violence and incidence of disease highlights the broader challenge of implementing health interventions in conflict areas. We discuss practical implications of this work in understanding and measuring the risks to polio eradication and other global health initiatives, and the policy implications of the need to reach vulnerable populations in conflict zones. [ABSTRACT FROM AUTHOR]

Prolonged excretion of poliovirus can occur in immunodeficient patients who receive oral polio vaccine, which may lead to propagation of highly divergent vaccine-derived polioviruses (VDPVs), posing a concern for global polio eradication. This study aimed to estimate the proportion of primary immunodeficient children with enterovirus infection and to identify the long-term polio/nonpolio enterovirus excreters in a tertiary care unit in Mumbai, India. During September 2014-April 2017, 151 patients received diagnoses of primary immunodeficiency (PID). We isolated 8 enteroviruses (3 polioviruses and 5 nonpolio enteroviruses) in cell culture of 105 fecal samples collected from 42 patients. Only 1 patient with severe combined immunodeficiency was identified as a long-term VDPV3 excreter (for 2 years after identification of infection). Our results show that the risk of enterovirus excretion among children in India with PID is low; however, systematic screening is necessary to identify long-term poliovirus excreters until the use of oral polio vaccine is stopped. [ABSTRACT FROM AUTHOR]

Objectives. Transmission of polio poses a threat to military forces when deploying to regions where such viruses are endemic. US-born soldiers generally enter service with immunity resulting from childhood immunization against polio; moreover, new recruits are routinely vaccinated with inactivated poliovirus vaccine (IPV), supplemented based upon deployment circumstances. Given residual protection from childhood vaccination, risk-based vaccination may sufficiently protect troops from polio transmission. Methods. This analysis employed a mathematical system for polio transmission within military populations interacting with locals in a polio-endemic region to evaluate changes in vaccination policy. Results. Removal of blanket immunization had no effect on simulated polio incidence among deployed military populations when risk-based immunization was employed; however, when these individuals reintegrated with their base populations, risk of transmission to nondeployed personnel increased by 19%. In the absence of both blanket- and risk-based immunization, transmission to nondeployed populations increased by 25%. The overall number of new infections among nondeployed populations was negligible for both scenarios due to high childhood immunization rates, partial protection against transmission conferred by IPV, and low global disease incidence levels. Conclusion. Risk-based immunization driven by deployment to polio-endemic regions is sufficient to prevent transmission among both deployed and nondeployed US military populations. [ABSTRACT FROM AUTHOR]

Background: Recent detections of circulating serotype 2 vaccine-derived poliovirus in northern Nigeria (Borno and Sokoto states) and Pakistan (Balochistan Province) and serotype 1 wild poliovirus in Pakistan, Afghanistan, and Nigeria (Borno) represent public health emergencies that require aggressive response.Methods: We demonstrate the importance of undervaccinated subpopulations, using an existing dynamic poliovirus transmission and oral poliovirus vaccine evolution model. We review the lessons learned during the polio endgame about the role of subpopulations in sustaining transmission, and we explore the implications of subpopulations for other vaccine-preventable disease eradication efforts.Results: Relatively isolated subpopulations benefit little from high surrounding population immunity to transmission and will sustain transmission as long as they do not attain high vaccination coverage. Failing to reach such subpopulations with high coverage represents the root cause of polio eradication delays. Achieving and maintaining eradication requires addressing the weakest links, which includes immunizing populations in insecure areas and/or with disrupted or poor-performing health systems and managing the risks of individuals with primary immunodeficiencies who can excrete vaccine-derived poliovirus long-term.Conclusions: Eradication efforts for vaccine-preventable diseases need to create performance expectations for countries to immunize all people living within their borders and maintain high coverage with appropriate interventions.Keywords. Polio; eradication; transmission; heterogeneity. [ABSTRACT FROM AUTHOR]

In 1988, the by the World Health Assembly established the Global Polio Eradication Initiative, which consisted of a partnership among the World Health Organization (WHO), Rotary International, the Centers for Disease Control and Prevention (CDC), and the United Nations Children's Fund. By 2016, the annual incidence of polio had decreased by >99.9%, compared with 1988, and at the time of writing, only 3 countries in which wild poliovirus circulation has never been interrupted remain: Afghanistan, Nigeria, and Pakistan. A key strategy for polio eradication has been the development of a skilled and deployable workforce to implement eradication activities across the globe. In 1999, the Stop Transmission of Polio (STOP) program was developed and initiated by the CDC, in collaboration with the WHO, to train and mobilize additional human resources to provide technical assistance to polio-endemic countries. STOP has also informed the development of other public health workforce capacity to support polio eradication efforts, including national STOP programs. In addition, the program has diversified to address measles and rubella elimination, data management and quality, and strengthening routine immunization programs. This article describes the STOP program and how it has contributed to polio eradication by building global public health workforce capacity. [ABSTRACT FROM AUTHOR]

In 2009, the international Stop Transmission of Polio (STOP) program began supporting the Global Polio Eradication Initiative in the Republic of South Sudan to address shortages of human resources and strengthen acute flaccid paralysis surveillance. Workforce capacity support is provided to the South Sudan Expanded Program on Immunization by STOP volunteers, implementing partners, and non-governmental organizations. In 2013, the Polio Technical Advisory Group recommended that South Sudan transition key technical support from external partners to national staff as part of the Polio Eradication and Endgame Strategic Plan, 2013-2018. To assist in this transition, the South Sudan Expanded Program on Immunization human resources development project was launched in 2015. This 3-year project aims to build national workforce capacity as a legacy of the STOP program by training 56 South Sudanese at national and state levels with the intent that participants would become Ministry of Health staff on their successful completion of the project. [ABSTRACT FROM AUTHOR]

States and the World Health Organization (WHO), an international organization that is mandated to respect the sovereignty of its member states, are still the leading actors in global health. This paper explores how this discrepancy inhibits the ability of global health partnerships to implement programmes in conflict-affected areas that are under the de facto control of rebel organizations. We concentrate on a single crucial case, the polio outbreak in Syria in 2013, analysing a variety of qualitative data-twenty semi-structured interviews with key actors, official documents, and media reports-in order to investigate the events that preceded and followed this event. The WHO's mandate to respect the Syrian government's sovereignty inhibited its ability to prevent, identify and contain the outbreak because the Assad regime refused it permission to operate in rebel-controlled areas. The polio outbreak was identified and contained by organizations operating outside the United Nations (UN) system that disregarded the Syrian government's sovereignty claims and cooperated with the militants. Thus, we identify a serious problem with so-called global health partnerships in which nation states and international organizations remain key actors. Such initiatives function well in situations where there is a capable state that is concerned with the welfare of its citizens and has exclusivity of jurisdiction over its territory. But they can encounter difficulties in areas where rebels challenge the state's sovereignty. Although the response to the Syrian polio outbreak was ultimately effective, it was reactive, ad hoc, slow and relied on personnel who had little experience. Global health partnerships would be more effective in conflict-affected areas if they put in place proactive and institutionalized plans to implement their programmes in regions outside government control. [ABSTRACT FROM AUTHOR]

Acute flaccid paralysis (AFP) surveillance is a key strategy used by the Global Polio Eradication Initiative (GPEI) to measure progress towards reaching the global eradication goal. Supported by a global polio laboratory network, AFP surveillance is conducted in 179 of 194 WHO member states. Active surveillance visits to priority health facilities are used to assure all children <15 years with AFP are detected, followed by stool specimen collection and testing for poliovirus in WHO-accredited polio laboratories. The quality of AFP surveillance is regularly monitored with standardized surveillance quality indicators. In highest risk countries and areas, the sensitivity of AFP surveillance is enhanced by environmental surveillance (testing of sewage samples). Genetic sequencing of detected poliovirus isolates yields programmatically important information on polio transmission pathways. AFP surveillance is one of the most valuable assets of the GPEI, with the potential to serve as a platform to build integrated disease surveillance systems. Continued support to maintain AFP surveillance systems will be essential, to reliably monitor the completion of global polio eradication, and to assure that a key resource for building surveillance capacity is transitioned post-eradication to support other health priorities. [ABSTRACT FROM AUTHOR]

An editorial is presented on the role of fractional-dose intradermal inactivated poliovirus vaccine (fIPV) in the global eradication of poliovirus. Focus is given to a study published within the issue on the role of single intradermal fIPV in boosting mucosal immunity, noting its significance in adopting fIPV recommendations. Considerations in the implementation of intradermal fIPV in routine immunization program are noted.

The polio eradication programme in Nigeria has been successful in reducing incidence to just six confirmed cases in 2014 and zero to date in 2015, but prediction and management of future outbreaks remains a concern. A Poisson mixed effects model was used to describe poliovirus spread between January 2001 and November 2013, incorporating the strength of connectivity between districts (local government areas, LGAs) as estimated by three models of human mobility: simple distance, gravity and radiation models. Potential explanatory variables associated with the case numbers in each LGA were investigated and the model fit was tested by simulation. Spatial connectivity, the number of non-immune children under five years old, and season were associated with the incidence of poliomyelitis in an LGA (all P < 0.001). The best-fitting spatial model was the radiation model, outperforming the simple distance and gravity models (likelihood ratio test P < 0.05), under which the number of people estimated to move from an infected LGA to an uninfected LGA was strongly associated with the incidence of poliomyelitis in that LGA. We inferred transmission networks between LGAs based on this model and found these to be highly local, largely restricted to neighbouring LGAs (e.g. 67.7% of secondary spread from Kano was expected to occur within 10 km). The remaining secondary spread occurred along routes of high population movement. Poliovirus transmission in Nigeria is predominantly localised, occurring between spatially contiguous areas. Outbreak response should be guided by knowledge of high-probability pathways to ensure vulnerable children are protected. [ABSTRACT FROM AUTHOR]

Since 2005, Pakistan has witnessed a net increase in polio, reaching a 15-year crest in 2014 when 306 cases were reported. Pakistan, along with Afghanistan, is one the remaining two polio-endemic countries. The numbers of cases reported in Pakistan in 2014 were far in excess of Afghanistan (28) and Nigeria (6). This paper focuses on the endemic militancy plaguing the country that has recently created grave obstacles for countrywide polio eradication. We argue that the relationship between polio and militancy in Pakistan has had two facets. First, polio vaccination efforts have become a casualty of militancy: over the last decade, polio vaccination was periodically banned in militant strongholds, large cohorts of children remained unvaccinated in remote frontier regions as vaccinators were unable to reach them, and antivaccination discourses in many parts of the country deterred others from vaccinating their children. The second relationship between the presence of polio in Pakistan and militancy is one where state-led polio vaccination efforts became a target of militancy. This was through the deliberate killing of polio workers; since July 2012, 71 contractual government employees tasked with administering polio vaccines have been killed, posing impediments to vaccine coverage. This paper concludes that in addition to implementing policies to improve vaccination coverage, endemic militancy must be addressed before polio can be eradicated. [ABSTRACT FROM AUTHOR]

In 2009, India contributed to over half the global cases of poliomyelitis. Many believed that India would be the last country to be polio free. India proved them wrong and was certified polio free in 2014. In January 2016, India celebrated 5 years of being polio free. One of the major reasons behind the interruption of polio transmission in the Polio endemic states of Uttar Pradesh and Bihar was the deployment of Social Mobilization Network (SMNet). A three tiered structure, the 7300 strong SMNet is now the gold standard in public health communication. It mobilizes communities by spearheading civil society participation; and works at district, block and community levels. The SMNet's social mobilization has evolved into an accelerated approach for achieving results with principles of mobilization at its core. The SMNet targets resistance to polio immunization through a multipronged approach by using local religious leaders, community influencers, interpersonal communication, counseling, mothers meetings, announcements from religious institutions and rallies. The success of the SMNet has been its ability to identify and convert resistant families into advocates for polio immunization. Deeply respected in the community, the SMNet mobilizers (98 percent of whom are women) are themselves models for gender empowerment. The SMNet model shows how mobilization techniques can be harnessed for short term and long term goals and can be replicated in other health programs to achieve the same results as were achieved for Polio. [ABSTRACT FROM AUTHOR]

Background: Following the 2012 declaration by World Health Organization (WHO) Regional Director for Africa and the WHO Executive Board to ramp up routine immunization (RI) activities, began to intensify activities to strengthen RI. This study assessed how the intensification of RI helped strengthen service delivery in local government areas (LGAs) of northern Nigeria at high risk for polio transmission.Methods: A retrospective study was performed by analyzing RI administrative data and findings from supportive supervisory visits in 107 high-risk LGAs.Results: Our study revealed that administrative coverage with 3rd dose of diphtheria-pertussis-tetanus vaccine in the 107 high-risk LGAs improved from a maximum average coverage of 33% during the preintensification period of 2009-2011 to 74% during the postintensification period of 2012-2014.Conclusions: Routine immunization could be strengthened in areas where coverage is low, and RI has been identified to be weak when certain key routine activities are intensified. [ABSTRACT FROM AUTHOR]

Introduction: Nigeria is among the 3 countries in which polio remains endemic. The country made significant efforts to reduce polio transmission but remains challenged by poor-quality campaigns and poor team performance in some areas. This article demonstrates the application of geographic information system technology to track vaccination teams to monitor settlement coverage, reduce the number of missed settlements, and improve team performance.Methods: In each local government area where tracking was conducted, global positioning system-enabled Android phones were given to each team on a daily basis and were used to record team tracks. These tracks were uploaded to a dashboard to show the level of coverage and identify areas missed by the teams.Results: From 2012 to June 2015, tracking covered 119 immunization days. A total of 1149 tracking activities were conducted. Of these, 681 (59%) were implemented in Kano state. There was an improvement in the geographic coverage of settlements and an overall reduction in the number of missed settlements.Conclusions: The tracking of vaccination teams provided significant feedback during polio campaigns and enabled supervisors to evaluate performance of vaccination teams. The reports supported other polio program activities, such as review of microplans and the deployment of other interventions, for increasing population immunity in northern Nigeria. [ABSTRACT FROM AUTHOR]

The article presents a case study about a 2013 Polio crisis in Israel which involves the detection of wild-type Poliovirus 1 (WPV1) in Israel's sewage system, and it mentions the Israeli Ministry of Health's communication strategy for dealing with the public health crisis. Poliovirus and bivalent oral Polio vaccines are examined, along with infection prevention, a duty of disclosure, and the legal rights of parents to make autonomous decisions regarding their children.

As a possible route for invasion of the CNS, circulating poliovirus (PV) in the blood is believed to traverse the blood-brain barrier (BBB), resulting in paralytic poliomyelitis. However, the underlying mechanism is poorly understood. In this study, we demonstrated that mouse transferrin receptor 1 (mTfR1) is responsible for PV attachment to the cell surface, allowing invasion into the CNS via the BBB. PV interacts with the apical domain of mTfR1 on mouse brain capillary endothelial cells (MBEC4) in a dose-dependent manner via its capsid protein (VP1).Wefound that F-G, G-H, and H-I loops in VP1 are important for this binding. However, C-D, D-E, and E-F loops in VP1-fused Venus proteins efficiently penetrate MBEC4 cells. These results imply that the VP1 functional domain responsible for cell attachment is different from that involved in viral permeation of the brain capillary endothelium. We observed that cotreatment of MBEC4 cells with excess PV particles but not dextran resulted in blockage of transferrin transport into cells. Using the Transwell in vitro BBB model, transferrin co-treatment inhibited permeation of PV into MBEC4 cells and delayed further viral permeation via mTfR1 knockdown. With mTfR1 as a positive mediator of PV-host cell attachment and PV permeation of MBEC4 cells, our results indicate a novel role of TfR1 as a cellular receptor for human PV receptor/CD155-independent PV invasion of the CNS. [ABSTRACT FROM AUTHOR]

The possibility of periodic routine vaccination campaigns (PRVCs) is introduced in the context of a search for optimal oral poliovirus vaccine (OPV) administration strategies. Like the usual continuous routine vaccination campaign (CRVC), PRVCs target only newborns. However, they are not necessarily implemented continuously in time. Using a dynamic and compartmental polio transmission model in a stochastic context, it is shown that some PRVCs can achieve much greater efficiency than CRVC in terms of probability of wild poliovirus (WPV) eradication, even though they never outperform CRVC in terms of total number of paralytic infections. Moreover, these PRVCs results can be obtained at a lower price than CRVC. It is also shown that, even though PRVCs do not perform better than pulse vaccination campaigns (PVCs) when only epidemiological outputs are valued, they can do so when a cost–benefit analysis is preferred. [ABSTRACT FROM AUTHOR]

A new deterministic model for the transmission dynamics of two strains of polio, the vaccine-derived polio virus (VDPV) and the wild polio virus (WPV), in a population is designed and rigorously analysed. It is shown that Oral Polio Vaccine (OPV) reversion (leading to increased incidences of WPV and VDPV strains), together with the combined effect of vaccinating a fraction of the unvaccinated susceptible and missed susceptible children, could induce the phenomenon of backward bifurcation when the associated reproduction number of the model is less than unity. Furthermore, the model undergoes competitive exclusion, where the strain with the higher reproduction number (greater than unity) drives the other (with reproduction number less than unity) to extinction. In the absence of OPV reversions (leading to the co-existence of both strains in the population), it is shown that the disease-free equilibrium of the model is globally-asymptotically stable whenever the associated reproduction number is less than unity. Numerical simulations of the model suggest that the model undergoes the phenomenon of competitive exclusion, where the strain with the higher reproduction number (greater than unity) drives the other to extinction. Furthermore, co-existence of the two strains is feasible if their respective reproduction number are equal or approximately equal (and greater than unity). [ABSTRACT FROM AUTHOR]