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BACKGROUND Outbreaks of circulating vaccine-derived polioviruses (cVDPVs) pose a threat to the eventual eradication of all polioviruses. In 2017, an outbreak of cVDPV type 2 (cVDPV2) occurred in the midst of a war in Syria. We describe vaccination-based risk factors for and the successful response to the outbreak. METHODS We performed a descriptive analysis of cVDPV2 cases and key indicators of poliovirus surveillance and vaccination activities during 2016-2018. In the absence of reliable subnational coverage data, we used the caregiver-reported vaccination status of children with non-polio acute flaccid paralysis (AFP) as a proxy for vaccination coverage. We then estimated the relative odds of being unvaccinated against polio, comparing children in areas affected by the outbreak to children in other parts of Syria in order to establish the presence of poliovirus immunity gaps in outbreak affected areas. FINDINGS A total of 74 cVDPV2 cases were reported, with paralysis onset ranging from 3 March to 21 September 2017. All but three cases were reported from Deir-ez-Zor governorate and 84% had received

Since 1988, when World Health Organization (WHO) Member States and partners launched the Global Polio Eradication Initiative, the number of wild poliovirus (WPV) cases has declined from 350,000 in 125 countries to 176 in only two countries in 2019 (1). The Global Commission for the Certification of Poliomyelitis Eradication (GCC) declared two of the three WPV types, type 2 (WPV2) and type 3 (WPV3), eradicated globally in 2015 and 2019, respectively (1). Wild poliovirus type 1 (WPV1) remains endemic in Afghanistan and Pakistan (1). Containment under strict biorisk management measures is vital to prevent reintroduction of eradicated polioviruses into communities from poliovirus facilities. In 2015, Member States committed to contain type 2 polioviruses (PV2) in poliovirus-essential facilities (PEFs) certified in accordance with a global standard (2). Member states agreed to report national PV2 inventories annually, destroy unneeded PV2 materials, and, if retaining PV2 materials, establish national authorities for containment (NACs) and a PEF auditing process. Since declaration of WPV3 eradication in October 2019, these activities are also required with WPV3 materials. Despite challenges faced during 2019-2020, including the coronavirus disease 2019 (COVID-19) pandemic, the global poliovirus containment program continues to work toward important milestones. To maintain progress, all WHO Member States are urged to adhere to the agreed containment resolutions, including officially establishing legally empowered NACs and submission of PEF Certificates of Participation.

Since the Global Polio Eradication Initiative (GPEI) was launched in 1988, the number of polio cases worldwide has declined approximately 99.99%; only two countries (Afghanistan and Pakistan) have never interrupted wild poliovirus (WPV) transmission (1). The primary means of detecting poliovirus circulation is through surveillance for acute flaccid paralysis (AFP) among children aged

Since the 1988 inception of the Global Polio Eradication Initiative (GPEI), progress toward interruption of wild poliovirus (WPV) transmission has occurred mostly through extensive use of oral poliovirus vaccine (OPV) in mass vaccination campaigns and through routine immunization services (1,2). However, because OPV contains live, attenuated virus, it carries the rare risk for reversion to neurovirulence. In areas with very low OPV coverage, prolonged transmission of vaccine-associated viruses can lead to the emergence of vaccine-derived polioviruses (VDPVs), which can cause outbreaks of paralytic poliomyelitis. Although WPV type 2 has not been detected since 1999, and was declared eradicated in 2015,* most VDPV outbreaks have been attributable to VDPV serotype 2 (VDPV2) (3,4). After the synchronized global switch from trivalent OPV (tOPV) (containing vaccine virus types 1, 2, and 3) to bivalent OPV (bOPV) (types 1 and 3) in April 2016 (5), GPEI regards any VDPV2 emergence as a public health emergency (6,7). During May-June 2017, VDPV2 was isolated from stool specimens from two children with acute flaccid paralysis (AFP) in Deir-ez-Zor governorate, Syria. The first isolate differed from Sabin vaccine virus by 22 nucleotides in the VP1 coding region (903 nucleotides). Genetic sequence analysis linked the two cases, confirming an outbreak of circulating VDPV2 (cVDPV2). Poliovirus surveillance activities were intensified, and three rounds of vaccination campaigns, aimed at children aged

The Global Polio Eradication Initiative (GPEI) has made substantial progress since its launch in 1988; only 37 wild poliovirus type 1 (WPV1) cases were detected in 2016, the lowest annual count ever. Wild poliovirus type 3 has not been detected since November 2012, and wild poliovirus type 2 was officially declared eradicated in September 2015. This success is attributable to the wide use of live oral poliovirus vaccines (OPVs). Since 2001, numerous outbreaks were caused by the emergence of genetically divergent vaccine-derived polioviruses (VDPVs) whose genetic drift from the parental OPV strains indicates prolonged replication or circulation (1). In 2015, circulating VDPV type 2 (cVDPV2) outbreaks were detected in five countries worldwide (Nigeria, Pakistan, Guinea, Burma, and South Sudan), and VDPV2 single events were reported in 22 countries. These events prompted the GPEI to withdraw the type 2 component (Sabin2) of trivalent OPV (tOPV) in a globally coordinated, synchronized manner in April 2016 (2,3), at which time all OPV-using countries switched to using bivalent OPV (bOPV), containing Sabin types 1 and 3. This report details for the first time the virologic tracking of elimination of a live vaccine that has been withdrawn from routine and mass immunization systems worldwide (3). To secure elimination, further monitoring is warranted to detect any use of tOPV or monovalent OPV type 2 (mOPV2).

Laboratories need leaders who can effectively utilize the laboratories' resources, maximize the laboratories'capacity to detect disease, and advocate for laboratories in a fluctuating health care environment. To address this need, the University of Washington, USA, created the Certificate Program in Laboratory Leadership and Management in partnership with WHO Regional Office for the Eastern Mediterranean, and implemented it with 17 participants and 11 mentors from clinical and public health laboratories in 10 countries (Egypt, Iraq, Jordan, Lebanon, Morocco, Oman, Pakistan, Qatar, Saudi Arabia, and Yemen) in 2014. Designed to teach leadership and management skills to laboratory supervisors, the programme enabled participants to improve laboratory testing quality and operations. The programme was successful overall, with 80% of participants completing it and making impactful changes in their laboratories. This success is encouraging and could serve as a model to further strengthen laboratory capacity in the Region.تنفيذ برنامج للتطوير المهني بالتوجيه في مجال قيادة وإدارة المختبرات في الشرق الأوسط وأفريقيا.لوسي برون، ديبورا كونفر، إليزابيث سكوت، لورا ليفينغستون، كاتلن برادبورن، أليكس ماك غي، توم فورتوانغلر، آن داونر، علي مُقداد، جين فريدريك فلاندين، سالماز شوتورباني، هومايون أصغر، ه. ي. طلبة، ه. جي. أحمد، علاء العلوان، روبرت مارتين.تحتاج المخترات لقادة يمكنهم الانتفاع مما فيها من موارد بفعالية، وتعظيم قدراتها لأقى قدر يتيح كشف الأمراض، ويدافعون عنها في بيئة متقلبة للرعاية الصحية. ولتلبية هذه الحاجة، أنشأت جامعة واشنطن في الولايات المتحدة الأمريكية برنامجاً لنيل شهادة القيادة والإدارة للمخترات بالشراكة مع المكتب الإقليمي لرق المتوسط لمنظمة الصحة العالمية، وفي عام 2014 تم تنفيذ البرنامج الذي ضم 17 مشاركاً و 11 موجِّهاً ينتمون إلى المخترات السريرية ومخترات الصحة العامة في 10 بلدان (مر والعراق والأردن ولبنان والمغرب وعُان وباكستان وقطر والمملكة العربية السعودية واليمن). وانطلاقاً من كون البرنامج قد تم تصميمه لتعليم المشرفن عى المخترات مهارات القيادة والإدارة، فقد وفّر البرنامج للمشاركين فيه إمكانية تحسن جودة الاختبارات والعمليات. ولقد كان البرنامج ناجحاً عى وجه الإجمال، فقد أكمل % 80 من المشاركين مشاركتهم به، وأحدثوا تغيرات ذات مردود ملحوظ في المخترات التي يعملون فيها. ويبدو نجاح البرنامج مشجعاً ويمكن أن يكون نموذجاً لتطوير المزيد من القدرات في المخترات في الإقليم.Mise en oeuvre d’un programme de mentorat en développement professionnel pour les directeurs et les cadres de laboratoire au Moyen-Orient et en Afrique du Nord.Les laboratoires ont besoin de directeurs à même d’utiliser les ressources internes de façon efficace, de maximiser leurs capacités à dépister les maladies, et d’oeuvrer pour le bien de ces établissements dans un environment de soins de santé en perpétuel changement. Pour répondre à ces besoins, l’Université de Washington (États-Unis), en partenariat avec le Bureau régional de l’OMS pour la Méditerranée orientale, a mis au point le Programme de certification en direction et gestion de laboratoire qui a été suivi par 17 participants et 11 mentors issus de laboratoires de santé clinique et publique dans 10 pays (Arabie saoudite, Égypte, Iraq, Jordanie, Liban, Maroc, Oman, Pakistan, Qatar et Yémen) au cours de l’année 2014. Conçu pour former les responsables de laboratoire aux compétences de direction et de gestion, le programme a permis aux participants de renforcer la qualité du dépistage et des opérations de leurs laboratoires. Le programme a été une réussite dans l’ensemble puisqu’il a été suivi jusqu’à son terme par 80 % des participants et que ceux-ci ont ensuite pu mettre en place des changements réels dans leurs laboratoires. Ce succès est encourageant et pourrait servir de modèle afin de renforcer davantage encore les capacités des laboratoires dans la Région.

Background Enteroviruses are common human pathogens occasionally associated with severe disease, notoriously paralytic poliomyelitis caused by poliovirus. Other enterovirus serotypes such as enterovirus A71 and D68 have been linked to severe neurological syndromes. New enterovirus serotypes continue to emerge, some believed to be derived from nonhuman primates. However, little is known about the circulation patterns of many enterovirus serotypes and, in particular, the detailed enterovirus composition of sewage samples. Methods We used a next-generation sequencing approach analyzing reverse transcriptase polymerase chain reaction products synthesized directly from sewage concentrates. Results We determined whole-capsid genome sequences of multiple enterovirus strains from all 4 A to D species present in environmental samples from the United Kingdom, Senegal, and Pakistan. Conclusions Our results indicate complex enterovirus circulation patterns in human populations with differences in serotype composition between samples and evidence of sustained and widespread circulation of many enterovirus serotypes. Our analyses revealed known and divergent enterovirus strains, some of public health relevance and genetically linked to clinical isolates. Enteroviruses identified in sewage included vaccine-derived poliovirus and enterovirus D-68 stains, new enterovirus A71 and coxsackievirus A16 genogroups indigenous to Pakistan, and many strains from rarely reported serotypes. We show how this approach can be used for the early detection of emerging pathogens and to improve our understanding of enterovirus circulation in humans.

Individuals with primary immunodeficiency disorder may excrete poliovirus for extended periods and will constitute the only remaining reservoir of virus after eradication and withdrawal of oral poliovirus vaccine. Here, we analyzed the epidemiology of prolonged and chronic immunodeficiency-related vaccine-derived poliovirus cases in a registry maintained by the World Health Organization, to identify risk factors and determine the length of excretion. Between 1962 and 2016, there were 101 cases, with 94/101 (93%) prolonged excretors and 7/101 (7%) chronic excretors. We documented an increase in incidence in recent decades, with a shift toward middle-income countries, and a predominance of poliovirus type 2 in 73/101 (72%) cases. The median length of excretion was 1.3 years (95% confidence interval: 1.0, 1.4) and 90% of individuals stopped excreting after 3.7 years. Common variable immunodeficiency syndrome and residence in high-income countries were risk factors for long-term excretion. The changing epidemiology of cases, manifested by the greater incidence in recent decades and a shift to from high- to middle-income countries, highlights the expanding risk of poliovirus transmission after oral poliovirus vaccine cessation. To better quantify and reduce this risk, more sensitive surveillance and effective antiviral therapies are needed.

This article summarizes the status of environmental surveillance (ES) used by the Global Polio Eradication Initiative, provides the rationale for ES, gives examples of ES methods and findings, and summarizes how these data are used to achieve poliovirus eradication. ES complements clinical acute flaccid paralysis (AFP) surveillance for possible polio cases. ES detects poliovirus circulation in environmental sewage and is used to monitor transmission in communities. If detected, the genetic sequences of polioviruses isolated from ES are compared with those of isolates from clinical cases to evaluate the relationships among viruses. To evaluate poliovirus transmission, ES programs must be developed in a manner that is sensitive, with sufficiently frequent sampling, appropriate isolation methods, and specifically targeted sampling sites in locations at highest risk for poliovirus transmission. After poliovirus ceased to be detected in human cases, ES documented the absence of endemic WPV transmission and detected imported WPV. ES provides valuable information, particularly in high-density populations where AFP surveillance is of poor quality, persistent virus circulation is suspected, or frequent virus reintroduction is perceived. Given the benefits of ES, GPEI plans to continue and expand ES as part of its strategic plan and as a supplement to AFP surveillance.

Background: If exposed to oral poliovirus vaccine (OPV), persons with primary immune deficiency disorders (PID) are at increased risk of paralytic poliomyelitis; and can chronically excrete poliovirus. However, the risk of excretion of vaccine derived poliovirus among immunodeficient persons (iVDPV) is not well characterized. We present summary of data from poliovirus surveillance project among PID patients collected between 2011 and 2014 from 11 Egyptian Governorates. Methods: Stool was tested for polioviruses in suspected or confirmed PID children regardless of whether Acute Flaccid Paralysis (AFP) was present or not. Those excreting poliovirus were followed until three consecutive negative stool samples were obtained. Results: There were 122 patients with suspected or confirmed PID identified; 13/122 (11%) excreted poliovirus; of these, 6 excreted iVDPVs, the remaining 7 excreted Sabin virus. The duration of iVDPV excretion ranged from 1 to 21 months. AFP was detected in 3/6 (50%) of those excreting iVDPVs. All iVDPV excretors had history of receiving OPV. Conclusions: Chronic poliovirus excretion in PID patients is rare, however, poliovirus eradication requires removal of all polioviruses from circulation; and because PID individuals are not necessarily paralyzed they might be missed by current poliovirus surveillance based on detection of AFP. To achieve poliovirus eradication, surveillance for polioviruses among PID patients should be routinely conducted in all countries, and poliovirus antiviral therapy must be made available for those with chronic excretion.

Persons who have developed acute flaccid paralysis following infection with wild-type polioviruses or vaccine-associated paralytic poliomyelitis usually excrete polioviruses for only a few weeks. However, some patients with paralytic poliomyelitis have had prolonged excretion of polioviruses for periods of up to 10 years after onset of disease. Most prolonged excretors have been identified in industrialized countries. We studied 348 patients 2-28 years old in Ethiopia, Pakistan and Guatemala with residual paralytic poliomyelitis to determine if they had IgA or IgG deficiency or persistent poliomyelitis excretion at least 1 year after onset of disease. None of the 348 affected individuals had IgG deficiency or persistent poliovirus excretion. One child had borderline low serum IgA concentration. Since we did not study children under 2 years of age, persons born with IgG deficiency disorders may have died in developing countries where replacement immunoglobulin therapy is not readily available. Nevertheless, persistent poliovirus excretion among persons 2 years of age and older with residual paralytic poliomyelitis is uncommon in developing countries.

Examination of sewage specimens for poliovirus (environmental surveillance) was adopted as a supplementary tool in the surveillance of poliomyelitis in Egypt. Sewage samples were concentrated about 50-fold using a simple two-phase separation technique, and inoculated in cell cultures in two collaborating laboratories in parallel. All but 9 of the 293 (97%) samples collected from January 2001 to December 2002 contained poliovirus and/or other enteroviruses, with polioviruses being detected in 84% of the samples. The proportion of specimens containing type 1 wild poliovirus (PV1W, the North-East African (NEAF) genotype) was less in 2002 (16%) than in 2001 (57%), and further decreased in 2003. While the overall sensitivity to detect PV1W was similar in the two collaborating laboratories, the specimens scored positive were not identical. Parallel cultures inoculated with aliquots of a given specimen very frequently resulted in isolation of different viruses. Moreover, partial sequence analysis occasionally revealed representatives of different genetic lineages of PV1W in a given specimen. These results emphasize the need to use intensive laboratory analysis to optimise sample sensitivity in environmental poliovirus surveillance, and the difficulties in reproducing the isolation results by simple re-inoculation of samples containing a mixture of different viruses.