Validation of improved automated nucleic acid extraction methods for direct detection of polioviruses for global polio eradication

Polioviruses (PV), the main causative agent of acute flaccid paralysis (AFP), are positive-sense single-stranded RNA viruses of the family Picornaviridae. As we approach polio eradication, accurate and timely detection of poliovirus in stool from AFP cases becomes vital to success for the eradication efforts. Direct detection of PV from clinical diagnostic samples using nucleic acid (NA) extraction and real-time reverse transcriptase polymerase chain reaction (rRT-PCR) instead of the current standard method of virus isolation in culture, eliminates the long turn-around time to diagnosis and the need for high viral titer amplification in laboratories. An essential component of direct detection of PV from AFP surveillance samples is the efficient extraction of NA. Potential supply chain issues and lack of vendor presence in certain areas of the world necessitates the validation of multiple NA extraction methods. Using retrospective PV-positive surveillance samples (n=104), two extraction kits were compared to the previously validated Zymo Research Quick-RNA™ Viral Kit. The Roche High Pure Viral RNA Kit, a column-based manual extraction method, and the MagMaX™ Pathogen RNA/DNA kit used in the automated Kingfisher Flex system were both non-inferior to the Zymo kit, with similar rates of PV detection in pivotal rRT-PCR assays, such as pan-poliovirus (PanPV), poliovirus serotype 2 (PV2), and wild poliovirus serotype 1 (WPV1). These important assays allow the identification and differentiation of PV genotypes and serotypes and are fundamental to the GPLN program. Validation of two additional kits provides feasible alternatives to the current piloted method of NA extraction for poliovirus rRT-PCR assays.

Surveillance To Track Progress Toward Polio Eradication - Worldwide, 2022-2023

The reliable and timely detection of poliovirus cases through surveillance for acute flaccid paralysis (AFP), supplemented by environmental surveillance of sewage samples, is a critical component of the polio eradication program. Since 1988, the number of polio cases caused by wild poliovirus (WPV) has declined by >99.9%, and eradication of WPV serotypes 2 and 3 has been certified; only serotype 1 (WPV1) continues to circulate, and transmission remains endemic in Afghanistan and Pakistan. This surveillance update evaluated indicators from AFP surveillance, environmental surveillance for polioviruses, and Global Polio Laboratory Network performance data provided by 28 priority countries for the program during 2022-2023. No WPV1 cases have been detected outside of Afghanistan and Pakistan since August 2022, when an importation into Malawi and Mozambique resulted in an outbreak during 2021-2022. During 2022-2023, among 28 priority countries, 20 (71.4%) met national AFP surveillance indicator targets, and the number of environmental surveillance sites increased. However, low national rates of reported AFP cases in priority countries in 2023 might have resulted from surveillance reporting lags; substantial national and subnational AFP surveillance gaps persist. Maintaining high-quality surveillance is critical to achieving the goal of global polio eradication. Monitoring surveillance indicators is important to identifying gaps and guiding surveillance-strengthening activities, particularly in countries at high risk for poliovirus circulation.

Evaluation of the Acute flaccid paralysis surveillance indicators in Zambia from 2015-2021: a retrospective analysis

BACKGROUND

The resurgence of poliovirus infection in previously polio free regions and countries calls for renewed commitment to the global polio eradication efforts including strengthening of Acute Flaccid Paralysis (AFP) surveillance systems. Zambia is one of the countries substantially at risk for the importation of poliovirus infection from neighbouring countries including Malawi, Mozambique, and Democratic Republic of the Congo (DRC). This study describes a seven-year AFP surveillance, assesses the surveillance indicators, and highlights areas for improvement.

METHODS

We conducted retrospective analysis of the routinely collected AFP surveillance data from January 2015 to December 2022. The AFP surveillance indicators performance was assessed using the World Health Organisation's recommended minimum AFP surveillance indicators performance.

RESULTS

Cumulatively, a total of 1715 AFP cases were reported over the study period. More than half, 891 (52%) of reported cases were aged < 5 years with 917 (53.5%) of males. More than half, 1186 (69.2%) had fever at onset, 718 (41.9%) had asymmetric paralysis and 1164 (67.9%) had their paralysis progressed within 3 days of onset. The non-polio AFP rate ranges from 3.4 to 6.4 per 100,000 children < 15 years old and stool adequacy ranging from 70.9% to 90.2% indicating sensitive surveillance with late detection of cases. The percentage of cases with early stool collection, timely transportation was above the World Health Organisation (WHO) minimum of 80% but with declining proportion of stools arriving in the laboratory in optimal condition. Completeness of 60-days follow-up evaluation was suboptimal ranging from 0.9% to 28.2%.

CONCLUSION

The AFP surveillance system in Zambia is doing well. However, additional efforts are needed to improve early detection of cases; stool sample collection, transportation and monitoring to ensure arrival in good condition in the laboratory; and improve 60-days follow-up evaluation for evidenced-based classification of inadequate AFP cases and proper care.

Fully automated F-wave corridor extraction and analysis algorithm for F-wave analyses and MUNE studies

F-waves are used in motor unit number estimation (MUNE) studies, which require rapid dedicated software to perform calculations. The aim of this study is to define a mathematical method for a fully automated F-wave extraction algorithm to perform F-wave and MUNE studies while performing baseline corrections without distorting traces. Ten recordings from each class, such as healthy controls, polio patients and ALS patients, were included. Submaximal stimuli were applied to the median and ulnar nerves to record 300 traces from the abductor pollicis brevis and abductor digiti minimi muscles. The autocorrelation function and the signal of sum of all traces were used to find the location for the maximum amplitude of the F-waves. F-waves were revealed by using a cutting window. Linear line estimation was preferred for baseline corrections because it did not cause any distortion in the traces. The algorithm automatically revealed F-waves from all 30 recordings in accordance with the locations marked by a neurophysiologist. The execution of the algorithm was less than 2 (usually < 1) minutes when 300 traces were analyzed. Mean sMUP amplitudes and MUNE values are important for differentiating healthy controls from patients. Moreover, F-wave parameters belonging to polio patients on whom there was a relatively low number of studies conducted were also evaluated.

Experience and findings from surveillance peer review in Nigeria, August 2017-May 2019

Introduction

acute flaccid paralysis (AFP) surveillance is the gold standard of the Global Polio Eradication Initiative (GPEI) for detecting cases of poliomyelitis and tracking poliovirus transmission. Nigeria's AFP surveillance performance indicators are among the highest in countries of the World Health Organization (WHO) African Region. The primary AFP surveillance performance indicators are the rate of non-polio AFP among children and the proportion of timely, adequate specimen collection. The surveillance working group of the National Emergency Operations Centre assessed the quality of AFP surveillance data in some reportedly high-performing states.

Methods

we conducted a retrospective review of AFP surveillance performance indicators in Nigeria for 2010-2019. We also reviewed data in reports from four groups of surveillance peer reviews and validation visits (conducted by in-country GPEI partners) during August 2017-May 2019 in 16 states with high primary AFP surveillance indicators; the validation visits reviewed clinical information and the dates of specimen collection and onset of paralysis with caretakers.

Results

there were consistently increasing AFP surveillance primary performance indicators during 2010-2016, followed by declines during 2017-2019. From the data for 16 states with peer reviews conducted from August 2017-May 2019, overall concordance of reported and "true" (validated) AFP indicator data in peer review investigations was highly variable. True AFP concordance ranged from 58%-100%, and stool timeliness concordance ranged from 56%-95%. The most common clinical causes of reported AFP cases that were not true AFP were spastic paralysis, malaria, sickle cell disease, and malnutrition. All the states that participated in peer reviews developed surveillance improvement plans based on the gaps identified.

Conclusion

Nigeria has highly sensitive AFP surveillance according to reported primary AFP performance indicators. The findings of peer reviews indicate that the AFP surveillance system needs to be strengthened and well-supervised to enhance data quality.

Wastewater Testing and Detection of Poliovirus Type 2 Genetically Linked to Virus Isolated from a Paralytic Polio Case - New York, March 9-October 11, 2022

In July 2022, a case of paralytic poliomyelitis resulting from infection with vaccine-derived poliovirus (VDPV) type 2 (VDPV2)§ was confirmed in an unvaccinated adult resident of Rockland County, New York (1). As of August 10, 2022, poliovirus type 2 (PV2)¶ genetically linked to this VDPV2 had been detected in wastewater** in Rockland County and neighboring Orange County (1). This report describes the results of additional poliovirus testing of wastewater samples collected during March 9-October 11, 2022, and tested as of October 20, 2022, from 48 sewersheds (the community area served by a wastewater collection system) serving parts of Rockland County and 12 surrounding counties. Among 1,076 wastewater samples collected, 89 (8.3%) from 10 sewersheds tested positive for PV2. As part of a broad epidemiologic investigation, wastewater testing can provide information about where poliovirus might be circulating in a community in which a paralytic case has been identified; however, the most important public health actions for preventing paralytic poliomyelitis in the United States remain ongoing case detection through national acute flaccid myelitis (AFM) surveillance†† and improving vaccination coverage in undervaccinated communities. Although most persons in the United States are sufficiently immunized, unvaccinated or undervaccinated persons living or working in Kings, Orange, Queens, Rockland, or Sullivan counties, New York should complete the polio vaccination series as soon as possible.

What Is Polio?

This JAMA Patient Page discusses polio, including its epidemiology, prevention, and symptoms.

Investigation of airport sewage to detect importation of poliovirus, Poland, 2017 to 2020

BackgroundPolioviruses are human pathogens which may easily be imported via travellers from endemic areas and countries where oral polio vaccine (OPV) is still routinely used to polio-free countries. Risk of reintroduction strictly depends on polio immunisation coverage. Sustaining a polio-free status requires strategies that allow rapid detection and control of potential poliovirus reintroductions.AimThe aim of this study was to apply environmental surveillance at an international airport in Poland to estimate the probability of poliovirus importation via air transport.MethodsBetween 2017 and 2020, we collected 142 sewage samples at Warsaw Airport. After sewage concentration, virus was isolated in susceptible cell cultures. Poliovirus isolates were characterised by intratypic differentiation and sequencing.ResultsSeven samples were positive for polioviruses. All isolates were characterised as Sabin-like polioviruses type 3 (SL-3). No wild or vaccine-derived polioviruses were found. The number of mutations accumulated in most isolates suggested a limited circulation in humans. Only one SL-3 isolate contained seven mutations, which is compatible with more than half a year of circulation.ConclusionSince OPV was withdrawn from the immunisation schedule in Poland in 2016, detection of SL-3 in airport sewage may indicate the events of importation from a region where OPV is still in use. Our study shows that environmental surveillance, including airport sewage investigation, has the capacity to detect emerging polioviruses and monitor potential exposure to poliovirus importation. Poliovirus detection in sewage samples indicates the need for sustaining a high level of polio immunisation coverage in the population.

Surveillance to Track Progress Toward Polio Eradication - Worldwide, 2020-2021

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.

VaxArray immunoassay for the multiplexed quantification of poliovirus D-antigen

Next generation poliovirus vaccines are critical to reaching global poliovirus eradication goals. Recent efforts have focused on creating inactivated vaccines using attenuated Sabin strains that maintain patient safety benefits and immunogenicity of conventional inactivated vaccines while increasing manufacturing safety and lowering production costs, and on developing novel oral vaccines using modified Sabin strains that provide critical mucosal immunity but are further attenuated to minimize risk of reversion to neurovirulence. In addition, there is a push to improve the analytical tools for poliovirus vaccine characterization. Conventional and Sabin inactivated poliovirus vaccines typically rely on standard plate-based ELISA as in vitro D-antigen potency assays in combination with WHO international standards as calibrants. While widely utilized, the current D-antigen ELISA assays have a long time to result (up to 72 h), can suffer from lab-to-lab inconsistency due to non-standardized protocols and reagents, and are inherently singleplex. For D-antigen quantitation, we have developed the VaxArray Polio Assay Kit, a multiplexed, microarray-based immunoassay that uses poliovirus-specific human monoclonal antibodies currently under consideration as standardized reagents for characterizing inactivated Sabin and Salk vaccines. The VaxArray assay can simultaneously quantify all 3 poliovirus serotypes with a time to result of less than 3 h. Here we demonstrate that the assay has limits of quantification suitable for both bioprocess samples and final vaccines, excellent reproducibility and precision, and improved accuracy over an analogous plate-based ELISA. The assay is suitable for adjuvanted combination vaccines, as common vaccine additives and crude matrices do not interfere with quantification, and is intended as a high throughput, standardized quantitation tool to aid inactivated poliovirus vaccine manufacturers in streamlining vaccine development and manufacturing, aiding the global polio eradication effort.

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Multiplexed D-antigen immunoassay for all 3 poliovirus serotypes

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Has <3 h time to result and compares well to 3-day plate-based ELISA

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Assay shows high specificity and is reactive to sIPV, cIPV, and OPV

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Applicable to in-process samples, final IPV and combination vaccine formulations

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High accuracy and precision for both sIPV and cIPV over multiple users and days

Challenging definitions and diagnostic approaches for ancient rare diseases: The case of poliomyelitis

OBJECTIVE

This paper aims to contribute to the definition of ancient rare diseases in skeletons displaying pathologies associated with paralysis. It uses a new suite of methods, which can be applied to challenging cases of possible paralysis in archaeologically-derived human skeletal material, specifically applied to the identification of poliomyelitis.

MATERIALS

An adult male skeleton from Roman Halbturn, Austria.

METHODS

Morphological and entheseal change analyses, CT scans, X-rays, cross-section morphology, and histology, alongside modern clinical, as well as historic, literature were used to discuss paralyses.

RESULTS

The results suggest a diagnosis of poliomyelitis; now considered a rare disease, but perhaps ubiquitous in antiquity, thus complicating the definition of 'rare disease'.

CONCLUSIONS

The integrated methodological procedures employed for this case constitutes a replicable and thorough approach to diagnosis, and explores the nature of ancient rare diseases. Due to the socio-environmental aspects of poliomyelitis transmission, it is likely that polio was likely not rare in the past. Therefore, the definition of 'rare diseases in the past' must include rarely occurring rarely diagnosed diseases due to biases and challenges within the archaeological and environmental record.

SIGNIFICANCE

The developed suite of methods has not been applied to establish a diagnosis of polio in the past.

LIMITATIONS

The individual considered in this study is fairly well-preserved; thus, this set of analyses may not be applicable to all remains where preservation is poor or highly fragmentary, and the discussion of rare diseases requires relatively secure diagnoses and context.

SUGGESTIONS FOR FURTHER RESEARCH

Large collections and series of skeletal human remains are recommended to develop definitive conclusions.

Molecular epidemiology of enteroviruses and predominance of echovirus 30 in an Iranian population with aseptic meningitis

Human enteroviruses are the most prevalent causes of aseptic meningitis worldwide. However, despite such predominancy, defining the enteroviral etiology of aseptic meningitis remains a diagnostic dilemma for the clinician in Iran. Therefore, this study was conducted to characterize the prevalence and clinical significance of enteroviral aseptic meningitis as well as the predominant enterovirus serotypes among patients with aseptic meningitis in the South of Iran.Cerebrospinal fluid (CSF) specimens were obtained from 73 patients with aseptic meningitis (52.1% males and 47.9% females), ages ranging from 1 month to 88 years. Following the extraction of nucleic acid, the detection of enteroviruses was performed by RT-PCR, targeting the 5' untranslated region of the genome, and sequencing. Enteroviruses were found in 46.6% of samples (34/73). The most predominant serotype was echovirus 30, followed by coxsackievirus B5 and poliovirus type 1 Sabin strain. The enterovirus infections were more prevalent among female patients (58.8%) and those below 5 years of age (52.9%). Although enterovirus infections were observed throughout the year, the infections were more prevalent during autumn with fever as the predominant clinical symptom. The outcomes revealed that enteroviruses are significant causes of aseptic meningitis in the South of Iran, while suspected cases of aseptic meningitis are usually monitored by bacterial culture and biochemical testing of CSF samples. Therefore, the etiology remains unknown in most cases. Molecular detection of viral pathogens should be included as a common approach in the screening of patients with aseptic meningitis to prevent unnecessary treatment and to improve clinical management.

Acute Flaccid Myelitis

Acute flaccid myelitis (AFM) is an incompletely understood neurologic disorder occurring in epidemic fashion causing weakness ranging from mild paresis to devastating paralysis in children and some adults. This article reviews the case definition of AFM as well as its epidemiology and association with enteroviral infection. The clinical presentation, diagnostic investigation with particular attention to electrodiagnostics, acute management, and surgical options are described. Clinical outcomes and considerations for acute and long-term rehabilitation management are discussed extensively based on review of current literature, highlighting avenues for further study.

[HOW HEALTH SERVICES IN ISRAEL COPED WITH THE POLIO EPIDEMIC OF THE 1950'S]

Today, the introduction of a new medicine or vaccine or the clinical trial of some new potion requires the approval of a variety of bodies in accordance with Helsinki Agreement rules, National Health Laws and Health Ministry regulations. The creation of the World Health Organization (WHO) in 1946 added another essential layer to the firm base of principles governing the conduct of clinical trials that exist today. Its main contribution was to create a new reality following The Second World War and the subsequent Nuremberg Trials. The Declaration of Helsinki was only adopted eighteen years later, in 1964. In its first years of independence the infant State of Israel was attacked by a serious outbreak of polio which claimed many victims - mostly children and youngsters. Infantile paralysis - poliomyelitis (polio) was then considered as being untreatable. The disease affected 0.1% of the population of Israel. In 1950, out of a total population of 1.2 million, 1,500 were infected by polio. The epidemic struck over three successive seasons and affected more than 3,000 victims. The mortality rate stood at 10%. Experts, charlatans and fame seekers all presented their inventions to the country - creams, medicines and research projects all designed to bring relief to the sick children. Against all these stood the newly formed Ministry of Health, determined to bring order to the chaos. The only trial conducted by the Health Ministry was unsuccessful, but it was accompanied by the most stringent controls that would not have shamed even today's researchers. The clinical trials of Zibaline were conducted in the early 60's, after the polio vaccine had been introduced and the epidemic had passed. The purpose of this paper is to examine the influence of medical ethics, norms and morals on the way that medical practice dealt with the epidemic at a time when there were no laws or rules.

Polio-Like Manifestation of Powassan Virus Infection with Anterior Horn Cell Involvement, Canada

Evidence of spinal cord involvement in Powassan virus infection is largely limited to mouse models. We report a case of a polio-like illness caused by Powassan virus infection in a 62-year-old man in Canada. Magnetic resonance imaging showed T2 hyperintensities in the anterior horns of the cervical spinal cord.

Characterising the costs of the Global Polio Laboratory Network: a survey-based analysis

OBJECTIVE

To characterise the costs, including for environmental surveillance (ES), of the Global Polio Laboratory Network (GPLN) that provides laboratory support to the Global Polio Eradication Initiative (GPEI).

DESIGN AND PARTICIPANTS

We conducted a survey of the network across 92 countries of the 146 GPLN laboratories plus three non-GPLN laboratories that concentrate environmental samples to collect information about their activities, characteristics and costs during 2016. We estimate the total costs using regression of reported responses and complementing the findings with GPEI data.

RESULTS

We received responses from 132 (89%) of the 149 laboratories, with variable response rates for individual questions. We estimate that processing samples of patients with acute flaccid paralysis leads to total costs of approximately $28 million per year (2016 US$) based on extrapolation from reported costs of $16 million, of which 61% were supported by internal (national) funds. Fifty-nine (45%) of the 132 responding laboratories reported supporting ES and we estimate an additional $5.3 million of recurring costs for ES activities performed by the laboratories. The reported costs do not include an estimated additional $10 million of annual global and regional costs to coordinate and support the GPLN. On average, the staff supported by funding for polio in the responding laboratories spent 30% of their time on non-polio activities. We estimate total costs for laboratory support of approximately $43 million (note that this estimate does not include any field or other non-laboratory costs of polio surveillance).

CONCLUSIONS

Although countries contribute significantly to the GPLN financing, many laboratories currently depend on GPEI funds, and these laboratories also support the laboratory component of surveillance activities for other diseases. Sustaining critical global surveillance for polioviruses and transitioning support for other disease programmes will require continued significant funding after polio certification.

[Polio and post-polio syndrome, viewed by patients and health professionals in primary care]

OBJECTIVE

Polio affects the quality of life of those who have suffered from it and causes health problems including the post-polio syndrome. The main goals of this work were to know the patients perspective of how they have been affected by the disease and establish the knowledge of post-polio syndrome among patients and primary health care professionals.

METHODS

Interpretive qualitative research based on the Grounded Theory carried out in two health-care centers in the city of Malaga, one of them with care-rural clinics. Four focal groups were established with the participation of thirteen patients and two focus groups with twenty-six professional participants. Intentional sampling is performed until saturation. The analysis follows an inductive strategy using the Atlas Ti5.2 software.

RESULTS

The people affected by polio reports their personal histories of suffering counteracted by strong family support and an active coping attitude, marked by great effort exertion, willpower and endurance. These people made a positive assessment of their lives minimising the limitations. They presented compatible symptoms with post-polio syndrome, which remain unidentified due to the lack of knowledge of it among patients and health-care professionals. The health care provided was considered deficient due to several causes as for instance lack of involvement, communication problems.

CONCLUSIONS

The day-to-day polio experience is focused on personal overcoming with major roles played by family support, difficult relationships with the healthcare system and lack of knowledge of the post-polio syndrome.

Clearing Vaccine-Derived Poliovirus Infection Following Hematopoietic Stem Cell Transplantation: a Case Report and Review of Literature

The use of oral poliovirus vaccine in a worldwide scale has led to a 99.9% decrease in annual incidence of wild-type poliomyelitis and the eradication of serotype 2 poliovirus. However, the emergence of vaccine-derived polioviruses (VDPVs) is endangering the eradication program. Patients with combined immunodeficiencies are at increased risk of both vaccine-associated poliomyelitis and prolonged asymptomatic infection with immunodeficiency-associated VDPVs (iVDPVs). Herein, we present a severe combined immunodeficiency patient with prolonged and asymptomatic iVDPV infection. He continued to shed poliovirus during immunoglobulin replacement therapy and cleared the infection following successful hematopoietic stem cell transplantation (HSCT). To explain the efficiency of HSCT in clearing the infection, we reviewed the literature for all reports of HSCT in iVDPV-excreting patients and discussed novel ideas about the role of different immune mechanisms, including cell-mediated interactions, in mounting immune responses against poliovirus infections. This study could provide further insights into the immune mechanisms contributing to the clearance of enteroviral infections.

Extending the utility of the WHO recommended assay for direct detection of enteroviruses from clinical specimen for resolving poliovirus co-infection

OBJECTIVES

In a polio-free world there might be reduced funding for poliovirus surveillance. There is therefore the need to ensure that enterovirologist globally, especially those outside the global polio laboratory network, can participate in poliovirus surveillance without neglecting their enterovirus type of interest. To accomplish this, assays are needed that allow such active participation.

RESULTS

In this study we describes a sensitive and specific utility extension of the recently recommended WHO RT-snPCR assay that enables independent detection of the three poliovirus types especially in cases of co-infection. More importantly, it piggy-backs on the first round PCR product of the WHO recommended assay and consequently ensures that enterovirologists interested in nonpolio enteroviruses can continue their investigations, and contribute significantly and specifically to poliovirus surveillance, by using the excess of their first round PCR product.

The role of supplementary environmental surveillance to complement acute flaccid paralysis surveillance for wild poliovirus in Pakistan - 2011-2013

Background

More than 99% of poliovirus infections are non-paralytic and therefore, not detected by acute flaccid paralysis (AFP) surveillance. Environmental surveillance (ES) can detect circulating polioviruses from sewage without relying on clinical presentation. With extensive ES and continued circulation of polioviruses, Pakistan presents a unique opportunity to quantify the impact of ES as a supplement to AFP surveillance on overall completeness and timeliness of poliovirus detection.

Methods

Genetic, geographic and temporal data were obtained for all wild poliovirus (WPV) isolates detected in Pakistan from January 2011 through December 2013. We used viral genetics to assess gaps in AFP surveillance and ES as measured by detection of ‘orphan viruses’ (≥1.5% different in VP1 capsid nucleotide sequence). We compared preceding detection of closely related circulating isolates (≥99% identity) detected by AFP surveillance or ES to determine which surveillance system first detected circulation before the presentation of each polio case.

Findings

A total of 1,127 WPV isolates were detected by AFP surveillance and ES in Pakistan from 2011–2013. AFP surveillance and ES combined exhibited fewer gaps (i.e., % orphan viruses) in detection than AFP surveillance alone (3.3% vs. 7.7%, respectively). ES detected circulation before AFP surveillance in nearly 60% of polio cases (200 of 346). For polio cases reported from provinces conducting ES, ES detected circulation nearly four months sooner on average (117.6 days) than did AFP surveillance.

Interpretation

Our findings suggest ES in Pakistan is providing earlier, more sensitive detection of wild polioviruses than AFP surveillance alone. Overall, targeted ES through strategic selection of sites has important implications in the eradication endgame strategy.

Faster Detection of Poliomyelitis Outbreaks to Support Polio Eradication

As the global eradication of poliomyelitis approaches the final stages, prompt detection of new outbreaks is critical to enable a fast and effective outbreak response. Surveillance relies on reporting of acute flaccid paralysis (AFP) cases and laboratory confirmation through isolation of poliovirus from stool. However, delayed sample collection and testing can delay outbreak detection. We investigated whether weekly testing for clusters of AFP by location and time, using the Kulldorff scan statistic, could provide an early warning for outbreaks in 20 countries. A mixed-effects regression model was used to predict background rates of nonpolio AFP at the district level. In Tajikistan and Congo, testing for AFP clusters would have resulted in an outbreak warning 39 and 11 days, respectively, before official confirmation of large outbreaks. This method has relatively high specificity and could be integrated into the current polio information system to support rapid outbreak response activities.

Polio Eradication Initiative in India: Deconstructing the GPEI

The Global Polio Eradication Initiative (GPEI) promised eradication of polio by the year 2000 and certification of eradication by 2005. The first deadline is already a matter of history. With the reporting of polio cases in 2004, the new deadline for polio eradication by 2004 is postponed further. This article seeks to argue that the scientific and technical bodies spearheading the GPEI, including the WHO, UNICEF, and the U.S. Centers for Disease Control, have formulated a conceptually flawed strategy and that it is not weak political will that is the central obstacle in this final push for global eradication. The validity of the claims of “near success” by the proponents of the GPEI is also examined in detail. By taking India as a case study, the authors examine the achievements of the GPEI in nine years of intense effort since 1995. They conclude that the GPEI is yet another exercise in mismanaging the health priorities and programs in developing countries in the era of globalization.

Who presents to our electroneurophysiology laboratory?

OBJECTIVE

To determine the distribution rate of Electroneuromyography diagnosis and correspondence between the preliminary diagnosis and final outcome.

METHODS

The retrospective study was conducted at the Department of Neurology, Harran University, Sanliurfa, Turkey, and comprised record of patients diagnosed with Electroneuromyography during a 24-month period from April 2011 to April 2013. SPSS 11.5 was used for data analysis.

RESULTS

Of the 4,230 cases reviewed, 1,946 (46%) showed normal Electroneuromyography findings despite pathological Electroneuromyography findings in 2,284(54%) cases. The most common diagnosis was carpal tunnel syndrome in 721(17%) patients, followed by polyneuropathy 312(7.4%), peripheral nerve injury 238(5.6%), brachial plexus lesion 180(4.3%), myopathy 114(2.7%), lumbar radiculopathy 108(2.6%), poliomyelitis 62(1.5%) and injection neuropathy 62(1.5%).

CONCLUSIONS

Off-label use of Electroneuromyography may be reduced by using electroneurophysiological laboratory rotation as well as adequate and comprehensive clinical evaluation of patients.

Modeling undetected live poliovirus circulation after apparent interruption of transmission: implications for surveillance and vaccination

BACKGROUND

Most poliovirus infections occur with no symptoms and this leads to the possibility of silent circulation, which complicates the confirmation of global goals to permanently end poliovirus transmission. Previous simple models based on hypothetical populations assumed perfect detection of symptomatic cases and suggested the need to observe no paralytic cases from wild polioviruses (WPVs) for approximately 3-4 years to achieve 95% confidence about eradication, but the complexities in real populations and the imperfect nature of surveillance require consideration.

METHODS

We revisit the probability of undetected poliovirus circulation using a more comprehensive model that reflects the conditions in a number of places with different characteristics related to WPV transmission, and we model the actual environmental WPV detection that occurred in Israel in 2013. We consider the analogous potential for undetected transmission of circulating vaccine-derived polioviruses. The model explicitly accounts for the impact of different vaccination activities before and after the last detected case of paralytic polio, different levels of surveillance, variability in transmissibility and neurovirulence among serotypes, and the possibility of asymptomatic participation in transmission by previously-vaccinated or infected individuals.

RESULTS

We find that prolonged circulation in the absence of cases and thus undetectable by case-based surveillance may occur if vaccination keeps population immunity close to but not over the threshold required for the interruption of transmission, as may occur in northwestern Nigeria for serotype 2 circulating vaccine-derived poliovirus in the event of insufficient tOPV use. Participation of IPV-vaccinated individuals in asymptomatic fecal-oral transmission may also contribute to extended transmission undetectable by case-based surveillance, as occurred in Israel. We also find that gaps or quality issues in surveillance could significantly reduce confidence about actual disruption. Maintaining high population immunity and high-quality surveillance for several years after the last detected polio cases will remain critical elements of the polio end game.

CONCLUSIONS

Countries will need to maintain vigilance in their surveillance for polioviruses and recognize that their risks of undetected circulation may differ as a function of their efforts to manage population immunity and to identify cases or circulating live polioviruses.

Modeling undetected live poliovirus circulation after apparent interruption of transmission: implications for surveillance and vaccination

BACKGROUND

Most poliovirus infections occur with no symptoms and this leads to the possibility of silent circulation, which complicates the confirmation of global goals to permanently end poliovirus transmission. Previous simple models based on hypothetical populations assumed perfect detection of symptomatic cases and suggested the need to observe no paralytic cases from wild polioviruses (WPVs) for approximately 3-4 years to achieve 95% confidence about eradication, but the complexities in real populations and the imperfect nature of surveillance require consideration.

METHODS

We revisit the probability of undetected poliovirus circulation using a more comprehensive model that reflects the conditions in a number of places with different characteristics related to WPV transmission, and we model the actual environmental WPV detection that occurred in Israel in 2013. We consider the analogous potential for undetected transmission of circulating vaccine-derived polioviruses. The model explicitly accounts for the impact of different vaccination activities before and after the last detected case of paralytic polio, different levels of surveillance, variability in transmissibility and neurovirulence among serotypes, and the possibility of asymptomatic participation in transmission by previously-vaccinated or infected individuals.

RESULTS

We find that prolonged circulation in the absence of cases and thus undetectable by case-based surveillance may occur if vaccination keeps population immunity close to but not over the threshold required for the interruption of transmission, as may occur in northwestern Nigeria for serotype 2 circulating vaccine-derived poliovirus in the event of insufficient tOPV use. Participation of IPV-vaccinated individuals in asymptomatic fecal-oral transmission may also contribute to extended transmission undetectable by case-based surveillance, as occurred in Israel. We also find that gaps or quality issues in surveillance could significantly reduce confidence about actual disruption. Maintaining high population immunity and high-quality surveillance for several years after the last detected polio cases will remain critical elements of the polio end game.

CONCLUSIONS

Countries will need to maintain vigilance in their surveillance for polioviruses and recognize that their risks of undetected circulation may differ as a function of their efforts to manage population immunity and to identify cases or circulating live polioviruses.

[Polio, the long walk to the endgame]

Although the WHO original target date for the global eradication of poliomyelitis was the year 2000 -thanks to vaccination and institutional, public and private, resources for that purpose-, in 2013 the disease remained endemic in three countries, Afghanistan, Pakistan and Nigeria, and some cases were described in five others. The circulation of wild type 1 poliovirus in Israel, Gaza and the West Bank and the cases in Syria were a wakeup call, as at that time there were polioviruses derived from the oral vaccine that are still circulating among the human population and can cause the development of the disease. Travelling "from" and "to" endemic areas are factors to consider in poliovirus exportation and in its spread when it reaches areas with poor immunogenicity. Wars, terrorism, intolerance, lack of culture and proliferation of anti-vaccine groups and the rise of the anti-vaccination movement are important factors in the maintenance and expansion of the virus and in the "non-vaccination" against it. Based on the international situation to date, the Emergency Committee of WHO met in May 2014 to address the problem. It is still necessary to enhance the knowledge of the disease and its agent. In the first case to perform a differential diagnosis of flaccid paralysis and to continue vaccination programs, and in the second case to keep studying and looking for the poliovirus in environmental samples, which is a model for the study of many other viruses.

[An ELISA system based on the specific class Y (IgY) antibodies from egg yolks for the quantitative determination of D-antigen in inactivated poliovirus vaccines]

The results of the construction of the first Russian ELISA system for the quantitative determination of D-antigen of 1-3 poliovirus types in the preparations of inactivated poliovirus vaccines are presented. For the first time, this kind of system is based on the use of specific antibodies of class Y (IgY) from egg yolks of immunized hens. It was shown that this ELISA system is specific, sufficiently sensitive, and can be used for quantitative determination of D-antigen of 1-3 poliovirus types in inactivated poliovirus vaccines.

Enteroviruses as a possible cause of hypertension, dilated cardiomyopathy (DCM) and hypertensive heart failure (HHF) in South western Nigeria

BACKGROUND

Human enteroviruses have long been associated with various diseases of man resulting into a wide range of acute symptoms involving the cardiac and skeletal muscles, central nervous system, pancreas, skin and mucous membranes.

OBJECTIVE

To assess the role of enteroviruses in the etiology of hypertension, DCM and HHF.

METHODS

We obtained stool specimens from 70 subjects comprising 65 patients and 5 controls and isolation was carried out on RD, L20B, HEp-2C and Vero cell lines and identified by neutralization with standard antisera (RIVM). Thirty-six enteroviruses were isolated and identified to be Coxsackieviruses-B5, A9, Echoviruses 1, 6, 7, 9, 11, 12, 22, 30 and Poliovirus type 1 and 3.

RESULTS

Three most frequently occurring enterovirus serotypes which constitute 60.0% of the 30 NPEV typed and 50.0% of all the isolates were Echoviruses, Coxsackie-B5-virus and Coxsackievirus-A9. Echoviruses constituted 50.0% of all the serotypes while Coxsackieviruses-B5 and A9 accounts for the 27.8 % and 5.6% respectively. Enteroviral isolation rate was higher in age groups 51 years and above. The percentage of study subjects who had Coxsackie-B5-viruses and echoviruses was significantly (P<0.05) higher in cases of hypertension, HHF and DCM than in control subjects. Coxackie-B5-virus, Echovirus-6 and Echovirus-11 were found in both study locations.

CONCLUSION

The findings of this study showed that Enteroviruses may likely be involved in the etiology of hypertension, DCM and HHF. Further studies would therefore be necessary for the prevention and control of these diseases.

Identification and control of a poliomyelitis outbreak in Xinjiang, China

BACKGROUND

The last case of infection with wild-type poliovirus indigenous to China was reported in 1994, and China was certified as a poliomyelitis-free region in 2000. In 2011, an outbreak of infection with imported wild-type poliovirus occurred in the province of Xinjiang.

METHODS

We conducted an investigation to guide the response to the outbreak, performed sequence analysis of the poliovirus type 1 capsid protein VP1 to determine the source, and carried out serologic and coverage surveys to assess the risk of viral propagation. Surveillance for acute flaccid paralysis was intensified to enhance case ascertainment.

RESULTS

Between July 3 and October 9, 2011, investigators identified 21 cases of infection with wild-type poliovirus and 23 clinically compatible cases in southern Xinjiang. Wild-type poliovirus type 1 was isolated from 14 of 673 contacts of patients with acute flaccid paralysis (2.1%) and from 13 of 491 healthy persons who were not in contact with affected persons (2.6%). Sequence analysis implicated an imported wild-type poliovirus that originated in Pakistan as the cause of the outbreak. A public health emergency was declared in Xinjiang after the outbreak was confirmed. Surveillance for acute flaccid paralysis was enhanced, with daily reporting from all public and private hospitals. Five rounds of vaccination with live, attenuated oral poliovirus vaccine (OPV) were conducted among children and adults, and 43 million doses of OPV were administered. Trivalent OPV was used in three rounds, and monovalent OPV type 1 was used in two rounds. The outbreak was stopped 1.5 months after laboratory confirmation of the index case.

CONCLUSIONS

The 2011 outbreak in China showed that poliomyelitis-free countries remain at risk for outbreaks while the poliovirus circulates anywhere in the world. Global eradication of poliomyelitis will benefit all countries, even those that are currently free of poliomyelitis.

Acute flaccid paralysis surveillance status and community awareness in pastoralist and semi-pastoralist communities of Ethiopia

BACKGROUND

Acute flaccid paralysis (AFP) surveillance is an essential component of the polio eradication strategy. The last laboratory confirmed wild poliovirus in Ethiopia was identified in April 2008. However, the country remains at risk for re-infection because of a number of silent areas and borders with high risk countries.

OBJECTIVE

Assess AFP surveillance status and community perception on AFP/Polio in semi pastoralist and pastoralist areas.

METHODS

Community and facility based cross-sectional survey was conducted complemented by Focus Group Discussions (FGD) from March - April, 2012. The study populations included District and health center AFP surveillance focal persons, WHO surveillance officers, community and religious leaders and women who delivered in the previous one year in purposively selected districts in Core Group Polio Project Implementation areas of Ethiopia.

RESULT

Interviews with health center and district AFP surveillance focal persons revealed deficiencies in training, supervision and feedback. The performance of AFP detection varied in the study districts and knowledge about polio and AFP detection was found to be low in the study communities.

CONCLUSION

There is a need to strengthen awareness of communities through targeted information, education and communication (IEC) interventions. Regular need-based training and supportive supervision should be conducted, involving all stakeholders including religious leaders and community leaders at each step of the awareness creation process, case detection and reporting and by giving special emphasis to silent and border districts.

Knowledge of mothers on poliomyelitis and other vaccine preventable diseases and vaccination status of children in pastoralist and semi-pastoralist areas of Ethiopia

BACKGROUND

Awareness and service utilization are key to polio eradication.

OBJECTIVE

Assess the knowledge of mothers on polio and other vaccine preventable diseases, and utilization of immunization services in pastoralist and semi-pastoralist areas in Ethiopia.

METHODS

A community-based cross sectional study using a multistage cluster sampling method involving women who delivered during the previous one year was conducted.

RESULTS

A total of 600 women were interviewed. Three hundred-and-five (50.8%) women said they knew what polio was. The time to initiate polio vaccination was correctly indicated to be at birth or within 2 weeks of birth by 224 (37.4%) women. Four hundred forty five (74.2%) women said they did not know how polio is transmitted Polio birth dose (Polio 0) and Polio 3 vaccine coverage were estimated at 32% and 37% respectively. Adjusting for other factors, knowledge of when polio vaccination starts was significantly associated with having a child vaccinated for Polio 3 (OR 95% CI = 3.45 (2.33- 5.11).

CONCLUSION

Knowledge of mothers about polio is low and a little more than one third were aware of when the initial vaccine dose should be administered. Providing detailed information on polio and the recommended vaccination schedule can contribute to improve immunization and hasten polio eradication.

Cross-border wild polio virus transmission in CORE Group Polio Project areas in Ethiopia

BACKGROUND

Ethiopia interrupted indigenous polio transmission in April 2008. However, it remains at risk of reinfection because of importation of polio virus from bordering countries.

OBJECTIVES

Assess polio immunization activities and risk of wild polio virus (WPV) importation in CORE Group Polio Project (CGPP) international border areas of Ethiopia.

METHODS

The study employed key informant interviews of community volunteers (CV), health extension workers (HEWs), program coordinators, managers and other stakeholders, as well as focus group discussions (FGDs) with community and religious leaders in six border districts (woredas) located in three regions of the country. It was conducted in March and April 2012.

RESULTS

Thirty-three key informant interviews and six FGDs were conducted. Immunization coverage was reported to be low and misconceptions about causes and transmission of polio were abundant. There was extensive cross-border movement of people for various reasons and mechanisms for prevention of cross-border polio transmission was almost non existent. AFP case detection and reporting was generally low.

CONCLUSION AND RECOMMENDATIONS

Cross-border transmission of polio can occur from several frontiers. Suggestions to control cross-border polio transmission included establishing and/or strengthening cross-border collaboration with responsible counterparts in neighboring countries by using existing cross-border forums and structures to create community awareness, share information and resources, design and implement strategies for identification of children who are eligible for vaccination or suspected AFP cases. In addition districts should coordinate supplemental immunization activities to coincide with when adjacent districts in neighboring countries are carrying out similar actions.

Linking community volunteer surveillance focal persons with health extension workers on polio surveillance

BACKGROUND

Inadequate involvement of community volunteers in vaccine preventable disease surveillance and lack of uniformity in the reporting channel.

OBJECTIVE

To identify factors affecting linkage of Community Volunteers Surveillance focal Persons (CVSFP) and HEWs/Woreda Health Offices, identify feasible and acceptable solution for strong linkage and sustainable implementation of the project.

METHOD

A qualitative study based on purposive convenient sampling method involving CVs, HEW, responsible officials on Health Extension Program (HEP) and CORE Group Ethiopia Polio Partner NGO's focal persons was conducted.

RESULT

A total of 26 discussants were interviewed in the study woredas. Training of community volunteers at enrollment was not uniform. Health Extension workers and CVs plan together, visit the community together, have periodic meeting and both are supervised by the woreda health office. Community volunteers report to HEWs or woreda health office. The HEWs complain that CVs are not available as required; some are not reporting to HEWs, HEWs are not involved in the training of volunteers. Community volunteers complain distant travel to woreda and kebele to report and for meeting.

CONCLUSION

The day to day working relation, the meeting forums, woreda level monitoring and feedback mechanism shows how well the work of CVs and relation with HEWs is recognized. No standard training procedure is followed. Volunteers are used as guide; distance travel with no/inadequate incentive can reduce commitment of volunteers. Misunderstanding of HEWs about the volunteers' private/obligatory work was a factor for loose relation.

Knowledge and practice of frontline health workers (Health Extension Workers and Community Volunteer Surveillance Focal Persons) towards acute flaccid paralysis (AFP) case detection and reporting in pastoralist and semi-pastoralist areas of Ethiopia

BACKGROUND

Front line workers in pastoralist and semi pastoralist areas are expected to play a vital role in detecting cases of Acute Flaccid Paralysis.

OBJECTIVE

Assess knowledge and practice of Heath Extension Workers (HEWs) and Community Volunteer Surveillance Focal Persons (CVSFPs) on AFP case detection and reporting.

METHODS

A cross sectional survey involving 70 Health Extension Workers (HEWs) and 71 Community Volunteer Surveillance Focal Persons (CVSFPs) was conducted in 9 districts in Core Group Polio Project Implementation areas of Ethiopia from March 1-April 30, 2013. Data were entered and analyzed using SPSS version 17.

RESULTS

Thirty four HEWs (48.6%) searched for AFP cases by going from house to house, while 27 (38.6%) did not perform any function specific to AFP surveillance. Twenty (28.2%) and 7 (9.9%) of CVSFPs respectively, indicated using a case definition of AFP which included paralysis and acute paralysis. Nine (12.7%) of the CVSPF provided responses that did not include paralysis while 22 CVSFPs (31.0%) did not know the case definition of AFP. Three HEWs and 9 CVSFPs claimed to have detected and reported AFP cases. Thirty-eight (53.5%) CVSFPs had received training on community-based surveillance while 33 (46.5%) had none. Thirty nine (54.9%) of the CVSFPs reported having received supervision during the last six months, 22 (31.0%) of whom reported having received feedback.

CONCLUSION

Inadequate pertinent knowledge on AFP and inadequate training and supervision appear to be obstacles for effective AFP detection by front line health workers in the study communities.

Lightning can strike twice: an unlucky patient of neurological interest

Poliomyelitis, once a worldwide epidemic, is becoming increasingly rare owing to the introduction of the polio vaccine in the 1950s. It is estimated that the number of cases of polio has reduced by 99% since the Global Polio Eradication Initiative (GPEI) started in 1988. Amyotrophic lateral sclerosis (ALS) is another relatively uncommon condition which also affects anterior horn cells with debilitating neurological, and deadly, consequences. An unusual case of an aggressive form of ALS developing in a 72-year-old patient with paralytic poliomyelitis in childhood is presented. Her initial presentation was puzzling, and our approach to the diagnostic dilemma is discussed.

Centers for Disease Control and Prevention (CDC). Expanding poliomyelitis and measles surveillance networks to establish surveillance for acute meningitis and encephalitis syndromes--Bangladesh, China, and India, 2006-2008

Quality surveillance is critical to the control and elimination of vaccine-preventable diseases (VPDs). A key strategy for enhancing VPD surveillance, outlined in the World Health Organization (WHO) Global Framework for Immunization Monitoring and Surveillance (GFIMS), is to expand and link existing VPD surveillance systems (particularly those developed for polio eradication and measles elimination) to include other priority VPDs. Since the launch of the Global Polio Eradication Initiative in 1988, the incidence of polio has decrease by 99% worldwide. A cornerstone of this success is a sensitive surveillance system based on the rapid and timely reporting of all acute flaccid paralysis (AFP) cases in children aged <15 years, with confirmatory diagnostic testing performed by laboratories that are part of a global network. As countries achieve polio-free status, many have expanded syndromic surveillance to include persons with rash and fever, and have built measles diagnostic capacity in existing polio reference laboratories. Acute meningitis/encephalitis syndrome (AMES) and acute encephalitis syndrome (AES) are candidates for expanded surveillance because they are most often caused by VPDs of public health importance for which confirmatory laboratory tests exist. Vaccine-preventable cases of encephalitis include approximately 68,000 Japanese encephalitis (JE) cases, resulting in 13,000-20,000 deaths each year in Asia. Moreover, although bacterial meningitis incidence in Asia is not as well-documented, pneumococcal and meningococcal meningitis outbreaks have been reported in Bangladesh and China, and the incidence of Haemophilus influenzae type b (Hib) meningitis in children aged <5 years in India has been estimated to be 7.1 per 100,000 population, similar to that in European countries before the introduction of vaccine. This report describes a prototype for expanding existing polio and measles surveillance networks in Bangladesh, China, and India to include surveillance for viral and bacterial vaccine-preventable causes of AMES and AES and presents data from 2006-2008.

Sabin and wild type polioviruses from children who presented with acute flaccid paralysis in Nigeria

BACKGROUND

Sensitive poliovirus surveillance to detect vaccine-derived-polioviruses will continue to increase in importance.

OBJECTIVE

Isolating and identifying poliovirus strains from children of pediatrics age in Nigeria.

METHODS

A total of 120 fecal samples were randomly collected from children under the age of five who presented with acute flaccid paralysis. Samples were tested by tissue culture technique and further characterized by intratypic differentiation testing using ELISA and PCR methods.

RESULTS

The study confirmed the presence of 22(18.3%) enteroviral isolates comprising 19(86.4%) polioviruses and 3(13.6%) non-polio enteroviruses. These 19 polioviruses include: Sabin-type poliovirus-1 (15.8%), poliovirus-2 (10.5%), poliovirus-3 (10.5%) and wild-type poliovirus-1 (63.2%) isolates. It showed that poliovirus infection was higher in children ages 6-11 months (18.9%), females (18.4%), northern states (91.0%) with no vaccination record (75.0%). Wild-type poliovirus-1 was isolated from the stool samples of 12(54.6%) children from northern states and in all age groups except 18-23 months. No significant differences (P >0.05) between poliovirus infection and age (18.9% vs. 17.7%; 81.9% vs. 18.2%) and sex (18.3% vs. 18.4%). There was significant differences (P<0.05) between poliovirus infection and location (91.0% vs. 9.0%) and history of polio vaccination (75.0% vs. 0.0%). No wild-type poliovirus was found in those with complete vaccination.

CONCLUSION

This study further confirms the presence of Sabin and wild-type poliovirus among children in Nigeria. The isolation of Sabin strain of poliovirus is advantageous to the polio eradication program as it is capable of inducing natural immunity in susceptible hosts. Transmission of wild-type poliovirus among children with incomplete vaccination poses a serious threat to polio eradication program in Nigeria. Environmental and serological surveillance with larger sample size are important for monitoring poliovirus circulation in Nigeria.

[Study on the Fast Testing Strategy for identifying the wild poliovirus I]

OBJECTIVE

To explore the Fast Testing Sstrategy (FTS) for wild poliovirus I (WP1).

METHODS

Epidemiological investigations were carried out on 671 students from WP1 epidemic areas in China. A set of real time RT-PCR assays, including panenterovirus testings (PE) assay, poliovirus serotypings (PS) assay and the assay distinguishing wild strain from vaccine strain of poliovirus I (DWV) were introduced into the screening program for WPV1 to replace the conventional RT-PCR, recommended by the China National Polio Laboratory (GNPL). Additionally, sensitivities of all the assays were assessed by poliovirus type I to III (Sabin stain) and the isolated WPV1.

RESULTS

(1) 33 non-poliovirus enterovirus (NPEV) cases were detected, with 16 polio vaccine-related cases including 5 polio I, 1 polio II, 3 polio III, 1 polio I + II, 4 polio I + III and 2 polio I + II + III. Three WPV1 cases were also detected in this study and confirmed by CNPL. (2) For polio virus vaccine strain, sensitivities of the set of real time RT-PCR assays ranged from 1 to 100 times than that of the in-house RT-PCR assay. The sensitivities of PE and PS assays for the detection of polio II were 100 times than that of the RT-PCR assay and the sensitivity of DWV assay used for the detection of polio I were 10 times than that of the RT-PCR assay. For WPV1, the sensitivity of three real time RT-PCR was 10 times hight than that of the RT-PCR assay.

CONCLUSION

The novel FTS for WPV1 suggested by this study would include PE, PS and DWV. It not only could greatly shorten the testing time but also more sensitive than the RT-PCR and suited for emergency detection for WPV1.

[West Nile virus poliomyelitis after a holiday in Egypt]

BACKGROUND

Due to the worldwide near-extinction of poliovirus infections an acute presentation of poliomyelitis in the Netherlands has become extremely rare. However, in the differential diagnosis of such a disease presentation other pathogens need to be considered as well.

CASE DESCRIPTION

A 44-year-old female presented with fever and a flaccid paresis of the left leg, following a holiday in Egypt. The laboratory investigation demonstrated an acute West Nile virus (WNV) infection, after which the diagnosis 'WNV poliomyelitis' was made.

CONCLUSION

WNV poliomyelitis is a rare neurological complication of an infection with the WNV. The areas in Europe where WNV transmission to humans occurs are expanding. In the future, the number of neurological disorders caused by WNV is likely to increase, also in the Netherlands.

[Control of poliomyelitis and enterovirus infection in several areas of Russian Federation]

AIM

Control of poliovirus circulation by study of material from patients with acute flaccid paralysis and contact individuals, from children of risk groups; molecular characteristics of isolated polioviruses; monitoring of circulation of polioviruses and nonpoliomyelitis enteroviruses in population and the environment.

MATERIALS AND METHODS

Isolation and study of polioviruses and nonpoliomyelitis enteroviruses from various sources was performed in accordance with WHO recommendations.

RESULTS

Prolonged persistence and circulation of vaccine related strains of polioviruses in children is demonstrated. Enterovirus serotypes that circulate in the population and the environment more frequently are determined. CONCLUSION. Long term control of poliomyelitis and acute flaccid paralysis in combination with additional control variants in children from risk groups and objects of the environment allowed to obtain valuable data on poliovirus and nonpoliomyelitis enteroviruses circulation for the Program of eradication of poliomyelitis.

Vaccine-derived poliomyelitis 12 years after infection in Minnesota

A 44-year-old woman with long-standing common variable immunodeficiency who was receiving intravenous immune globulin suddenly had paralysis of all four limbs and the respiratory muscles, resulting in death. Type 2 vaccine-derived poliovirus was isolated from stool. The viral capsid protein VP1 region had diverged from the vaccine strain at 12.3% of nucleotide positions, and the two attenuating substitutions had reverted to the wild-type sequence. Infection probably occurred 11.9 years earlier (95% confidence interval [CI], 10.9 to 13.2), when her child received the oral poliovirus vaccine. No secondary cases were identified among close contacts or 2038 screened health care workers. Patients with common variable immunodeficiency can be chronically infected with poliovirus, and poliomyelitis can develop despite treatment with intravenous immune globulin.