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Detecting the circulation of poliovirus in its early stages is paramount for swift public health action. While environmental surveillance (ES) is promising for enhancing early pathogen detection, the influence of spatial arrangement of ES sites on early detection remains unclear. Here, we aim to assess the early detection ability of ES by varying the number and location of ES sites using the simulation-based approach utilising geographic and demographic characteristics of South Africa as a case study of a non-endemic country. We developed a stochastic meta-population model among unimmunised children aged under 5 years old, assuming a single introduction of wild poliovirus serotype 1. We constructed six scenarios by combining three importation risk distributions (predicated on population size, approximations of international inbound travel volume and border crossing volume) with two ES site layout strategies (proportionate to population size and importation risks via land border crossings). We showed a modest number of strategically positioned ES sites can achieve a high early detection ability given assumed importation risks were geographically confined while dispersed importation risks reduced the effectiveness of ES. Our sensitivity analysis suggested that implementing the ES across large areas with low sampling frequency consistently resulted in a better early detection ability against various importation scenarios than implementing the ES in limited areas with high sampling frequency. Although we acknowledge the challenges of translating our simulated outcomes for real-world situations, our study has implications for deciding the scale and site selection of ES.

Surveillance and detection of polioviruses (PV) remain crucial to monitoring eradication progress. Intratypic differentiation (ITD) using the real-time RT-PCR kit is key to the surveillance workflow, where viruses are screened after cell culture isolation before a subset are verified by sequencing. The ITD kit is a series of real-time RT-PCR assays that screens cytopathic effect (CPE)-positive cell cultures using the standard WHO method for virus isolation. Because ITD screening is a critical procedure in the poliovirus identification workflow, validation of performance of real-time PCR platforms is a core requirement for the detection of poliovirus using the ITD kit. In addition, the continual update and improvement of the ITD assays to simplify interpretation in all platforms is necessary to ensure that all real-time machines are capable of detecting positive real-time signals. Four platforms (ABI7500 real-time systems, Bio-Rad CFX96, Stratagene MX3000P, and the Qiagen Rotor-Gene Q) were validated with the ITD kit and a redesigned poliovirus probe. The poliovirus probe in the real-time RT-PCR pan-poliovirus (PanPV) assay was re-designed with a double-quencher (Zen ™ ) to reduce background fluorescence and potential false negatives. The updated PanPV probe was evaluated with a panel consisting of 184 polioviruses and non-polio enteroviruses. To further validate the updated PanPV probe, the new assay was pilot tested in five Global Polio Laboratory Network (GPLN) laboratories (Madagascar, India, Philippines, Pakistan, and Democratic Republic of Congo). The updated PanPV probe performance was shown to reduce background fluorescence and decrease the number of false positives compared to the standard PanPV probe.

China had been free of wild-type poliovirus transmission and infection for nearly 20 years when a 2011 outbreak of imported wild-type poliovirus was identified in Xinjiang. Efforts to control the outbreak are described, including the administration of 44 million doses of vaccine. The World Health Assembly established the Global Polio Eradication Initiative in 1988. 1 , 2 The World Health Organization (WHO) Western Pacific region, including China, was certified as a poliomyelitis-free region in 2000. 3 However, the transmission of wild-type poliovirus has not yet been stopped in Afghanistan, Pakistan, or Nigeria. Globally, some countries have had outbreaks of imported wild-type poliovirus, and in others the circulation of outbreak strains has been reestablished. 4 China has the world's largest population (1.347 billion in 2011). 5 By 1963, live, attenuated oral poliovirus vaccine (OPV) was being administered in annual campaigns conducted during the winter. OPV has been included . . .

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.

Surveillance for acute flaccid paralysis (AFP) is a fundamental cornerstone of the global polio eradication initiative (GPEI). Active surveillance (with visits to health facilities) is a critical strategy of AFP surveillance systems for highly sensitive and timely detection of cases. Because of the extensive resources devoted to AFP surveillance, multiple opportunities exist for additional diseases to be added using GPEI assets, particularly because there is generally 1 district officer responsible for all disease surveillance. For this reason, integrated surveillance has become a standard practice in many countries, ranging from adding surveillance for measles and rubella to integrated disease surveillance for outbreak-prone diseases (integrated disease surveillance and response). This report outlines the current level of disease surveillance integration in 3 countries (Nepal, India, and Nigeria) and proposes that resources continue for long-term maintenance in resource-poor countries of AFP surveillance as a platform for surveillance of vaccine-preventable diseases and other outbreak-prone diseases.

Polioviruses are positive-sense, single-stranded RNA picornaviruses and the principal cause of poliomyelitis. Global poliovirus surveillance has relied on poliovirus isolation in cells, which may take a minimum of 10 days, involves maintaining two cell lines, and propagates virus in high titers. With eradication underway, a major objective of the Global Polio Eradication Initiative (GPEI) is to develop culture-independent detection of polioviruses as an alternative method to complement the current virus isolation technique. A culture-independent method on poliovirus-positive stool suspensions was assessed with commercially available recombinant soluble poliovirus receptor (PVR) coupled to Histidine (His) tags. Viral RNA was screened by quantitative real-time reverse transcription PCR using the poliovirus intratypic differentiation kit. Poliovirus recovery was optimized with PVR-His–tagged protein and buffers supplemented with polyethylene glycol. To validate the poliovirus-PVR–His tag purification assay, 182 poliovirus-positive stools of programmatic importance were parallel tested against the GPLN-accepted virus isolation method. The PVR-His tag enrichment method detected poliovirus in 164 of 171 poliovirus-positive stools, whereas the virus isolation method misidentified 38 stools as poliovirus-negative (McNemar χ 2 p <0.0001). Using this method in combination with RNA extraction, viral RNA recovery increased and showed similar (WPV1) or higher (Sabin 1) sensitivity than the World Health Organization accredited variation of the virus isolation method. The PVR-His enrichment method could be a viable addition to poliovirus surveillance; similar methods have the potential to capture other human pathogens such as EV71 using an appropriate soluble His tag receptor.

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.

Background The Enterovirus (EV) surveillance system is inadequate in densely populated cities in India. EV can be shed in feces for several weeks; these viruses are not easily inactivated and may persist in sewage for long periods. Surveillance and epidemiological study of EV-related disease is necessary. Methods In this study, we compare the EV found in sewage with clinically isolated samples. Tissue culture was used for isolation of the virus and serotype confirmed by enterovirus neutralization tests. Results We found positive cases for enterovirus from clinical and sewage samples and identified additional isolates as echovirus 9, 11, 25 & 30 by sequencing. Conclusion There is a close relation among the serotypes of enterovirus shed in stools and isolated from the environment but few serotypes which were detected in sewage samples were not found clinically and the few which were detected clinically not found in sewage because some viruses are difficult to detect by the cell culture method.This study will be helpful for the researchers who are working on polio and nonpolio enterovirus especially in the countries which are struggling for polio eradication.

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.

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. 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. 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. 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.