Maintaining the Region of the Americas free of polio: best practices for incident management support teams.

The Pan American Health Organization (PAHO) and its Member States have been leading the efforts to eradicate wild poliovirus in the Region of Americas since smallpox's successful elimination in 1971. The region became the first to be certified free of wild poliovirus in 1994. However, in July 2022, an unvaccinated patient with no recent travel history was diagnosed with poliomyelitis in the United States of America. In response to the emergence of a circulating vaccine-derived poliovirus in the United States, PAHO established the Polio Incident Management Support Team. This team has been coordinating response efforts, focusing on: coordination, planning, and monitoring; risk communication and community engagement; surveillance and case investigation; vaccination; and rapid response. In this paper, we identified and documented best practices observed following establishment of the Incident Management Support Team (September 2022-2023) through a comprehensive review and analysis of various data sources and country-specific data from the polio surveillance dashboard. The aim was to share these best practices, highlighting technical support and implementation of polio measures by Member States. Despite several challenges, the Americas region remains polio-free. Polio risk is declining, with a July 2023 assessment showing fewer countries at medium, high, and very high risk. This progress reflects improved immunization coverage, surveillance, containment, health determinants, and outbreak preparedness and response. The PAHO Polio Incident Management Support Team has played a key role in supporting these efforts.

La Organización Panamericana de la Salud (OPS) y sus Estados Miembros han liderado los esfuerzos para erradicar el poliovirus salvaje en la Región de las Américas desde la eliminación exitosa de la viruela en 1971. En 1994, la Región fue la primera en obtener la certificación de libre del poliovirus salvaje. Sin embargo, en julio del 2022, se diagnosticó poliomielitis a un paciente de Estados Unidos de América no vacunado y sin antecedentes de viajes recientes. Para responder a la aparición de un poliovirus circulante derivado de la vacuna en ese país, la OPS creó el equipo de apoyo a la gestión de incidentes de poliomielitis. Este equipo ha asumido la coordinación de los esfuerzos de respuesta y se ha centrado en la coordinación, la planificación y seguimiento; la comunicación de riesgos y la participación de la comunidad; la vigilancia e investigación de casos; la vacunación; y la respuesta rápida. En este artículo, se determinan y documentan las mejores prácticas observadas después de la creación del equipo de apoyo a la gestión de incidentes (septiembre del 2022-2023) mediante una revisión y un análisis pormenorizados de datos procedentes de diversas fuentes y de datos específicos de los países del panel de vigilancia de la poliomielitis. El objetivo fue poner en común estas mejores prácticas y resaltar el apoyo técnico y la aplicación de medidas contra la poliomielitis por parte de los Estados Miembros. A pesar de los diversos desafíos, la Región de las Américas se mantiene libre de poliomielitis. El riesgo de esta enfermedad es cada vez menor, y la evaluación de julio del 2023 muestra una disminución del número de países con un riesgo medio, alto o muy alto. Este progreso refleja la mejora de la cobertura de inmunización, la vigilancia, la contención, los determinantes de la salud y la preparación y respuesta ante brotes. El equipo de apoyo a la gestión de incidentes relacionados con la poliomielitis de la OPS ha desempeñado un papel fundamental para brindar apoyo a estas iniciativas.

Desde a eliminação bem-sucedida da varíola em 1971, a Organização Pan-Americana da Saúde (OPAS) e seus Estados Membros têm estado à frente de iniciativas para erradicar o poliovírus selvagem na Região das Américas. Em 1994, a região foi a primeira do mundo a ser certificada como livre do poliovírus selvagem. Entretanto, em julho de 2022, um paciente não vacinado e sem histórico de viagens recentes foi diagnosticado com poliomielite nos Estados Unidos da América. Em resposta ao surgimento de um poliovírus derivado de vacina circulante nos Estados Unidos, a OPAS criou a Equipe de Apoio à Gestão de Incidentes de Poliomielite. A equipe vem administrando os esforços de resposta, concentrando-se em: coordenação, planejamento e monitoramento; comunicação de risco e envolvimento da comunidade; vigilância e investigação de casos; vacinação; e resposta rápida. Neste documento, identificamos e documentamos as melhores práticas observadas após a criação da Equipe de Apoio à Gestão de Incidentes (setembro de 2022 a 2023) por meio de uma revisão e análise abrangentes de diversas fontes de dados e dados específicos de cada país fornecidos por meio do painel de vigilância da poliomielite. O objetivo foi compartilhar essas melhores práticas, destacando o apoio técnico e a implementação de medidas contra a poliomielite pelos Estados Membros. Apesar de vários desafios, a Região das Américas continua livre da poliomielite. Um levantamento de julho de 2023 demonstrou que o risco da poliomielite vem diminuindo, com menos países com risco médio, alto ou muito alto. Essa evolução é resultado de melhoras na cobertura vacinal, vigilância, contenção, preparação, determinantes de saúde e resposta a surtos. A Equipe de Apoio à Gestão de Incidentes de Poliomielite da OPAS foi fundamental para apoiar esses esforços.

Response to Vaccine-Derived Polioviruses Detected through Environmental Surveillance, Guatemala, 2019.

Guatemala implemented wastewater-based poliovirus surveillance in 2018, and three genetically unrelated vaccine-derived polioviruses (VDPVs) were detected in 2019. The Ministry of Health (MoH) response included event investigation through institutional and community retrospective case searches for acute flaccid paralysis (AFP) during 2018-2020 and a bivalent oral polio/measles, mumps, and rubella vaccination campaign in September 2019. This response was reviewed by an international expert team in July 2021. During the campaign, 93% of children 6 months <7 years of age received a polio-containing vaccine dose. No AFP cases were detected in the community search; institutional retrospective searches found 37% of unreported AFP cases in 2018‒2020. No additional VDPV was isolated from wastewater. No evidence of circulating VDPV was found; the 3 isolated VDPVs were classified as ambiguous VDPVs by the international team of experts. These detections highlight risk for poliomyelitis reemergence in countries with low polio vaccine coverage.

Lessons learned from the implementation of integrated serosurveillance of communicable diseases in the Americas.

Objective: Systematize the experience and identify challenges and lessons learned in the implementation of an initiative for integrated serosurveillance of communicable diseases using a multiplex bead assay in countries of the Americas. Methods: Documents produced in the initiative were compiled and reviewed. These included concept notes, internal working papers, regional meetings reports, and survey protocols from the three participating countries (Mexico, Paraguay, and Brazil) and two additional countries (Guyana and Guatemala) where serology for several communicable diseases was included in neglected tropical diseases surveys. Information was extracted and summarized to describe the experience and the most relevant challenges and lessons learned. Results: Implementing integrated serosurveys requires interprogrammatic and interdisciplinary work teams for the design of survey protocols to respond to key programmatic questions aligned to the needs of the countries. Valid laboratory results are critical and rely on the standardized installment and roll-out of laboratory techniques. Field teams require adequate training and supervision to properly implement survey procedures. The analysis and interpretation of serosurveys results should be antigen-specific, contextualizing the responses for each disease, and triangulated with programmatic and epidemiological data for making decisions tailored to specific population socioeconomic and ecologic contexts. Conclusions: Integrated serosurveillance as a complementary tool for functional epidemiological surveillance systems is feasible to use and key components should be considered: political engagement, technical engagement, and integrated planning. Aspects such as designing the protocol, selecting target populations and diseases, laboratory capacities, anticipating the capacities to analyze and interpret complex data, and how to use it are key.

The Global Landscape of Pediatric Bacterial Meningitis Data Reported to the World Health Organization-Coordinated Invasive Bacterial Vaccine-Preventable Disease Surveillance Network, 2014-2019.

BACKGROUND: The World Health Organization (WHO) coordinates the Global Invasive Bacterial Vaccine-Preventable Diseases (IB-VPD) Surveillance Network to support vaccine introduction decisions and use. The network was established to strengthen surveillance and laboratory confirmation of meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis. METHODS: Sentinel hospitals report cases of children <5 years of age hospitalized for suspected meningitis. Laboratories report confirmatory testing results and strain characterization tested by polymerase chain reaction. In 2019, the network included 123 laboratories that follow validated, standardized testing and reporting strategies. RESULTS: From 2014 through 2019, >137 000 suspected meningitis cases were reported by 58 participating countries, with 44.6% (n = 61 386) reported from countries in the WHO African Region. More than half (56.6%, n = 77 873) were among children <1 year of age, and 4.0% (n = 4010) died among those with reported disease outcome. Among suspected meningitis cases, 8.6% (n = 11 798) were classified as probable bacterial meningitis. One of 3 bacterial pathogens was identified in 30.3% (n = 3576) of these cases, namely S. pneumoniae (n = 2177 [60.9%]), H. influenzae (n = 633 [17.7%]), and N. meningitidis (n = 766 [21.4%]). Among confirmed bacterial meningitis cases with outcome reported, 11.0% died; case fatality ratio varied by pathogen (S. pneumoniae, 12.2%; H. influenzae, 6.1%; N. meningitidis, 11.0%). Among the 277 children who died with confirmed bacterial meningitis, 189 (68.2%) had confirmed S. pneumoniae. The proportion of pneumococcal cases with pneumococcal conjugate vaccine (PCV) serotypes decreased as the number of countries implementing PCV increased, from 77.8% (n = 273) to 47.5% (n = 248). Of 397 H. influenzae specimens serotyped, 49.1% (n = 195) were type b. Predominant N. meningitidis serogroups varied by region. CONCLUSIONS: This multitier, global surveillance network has supported countries in detecting and serotyping the 3 principal invasive bacterial pathogens that cause pediatric meningitis. Streptococcus pneumoniae was the most common bacterial pathogen detected globally despite the growing number of countries that have nationally introduced PCV. The large proportions of deaths due to S. pneumoniae reflect the high proportion of meningitis cases caused by this pathogen. This global network demonstrated a strong correlation between PCV introduction status and reduction in the proportion of pneumococcal meningitis infections caused by vaccine serotypes. Maintaining case-based, active surveillance with laboratory confirmation for prioritized vaccine-preventable diseases remains a critical component of the global agenda in public health.The World Health Organization (WHO)-coordinated Invasive Bacterial Vaccine-Preventable Disease (IB-VPD) Surveillance Network reported data from 2014 to 2019, contributing to the estimates of the disease burden and serotypes of pediatric meningitis caused by Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis.

Progress Toward Poliovirus Containment Implementation - Worldwide, 2019-2020.

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.

Surveillance to Track Progress Toward Polio Eradication - Worldwide, 2018-2019.

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 <15 years with testing of stool specimens for WPV and vaccine-derived polioviruses (VDPVs) (genetically reverted strains of the vaccine virus that regain neurovirulence) in World Health Organization (WHO)-accredited laboratories (2,3). In many locations, AFP surveillance is supplemented by environmental surveillance, the regular collection and testing of sewage to provide awareness of the extent and duration of poliovirus circulation (3). This report presents 2018-2019 poliovirus surveillance data, focusing on 40 priority countries* with WPV or VDPV outbreaks or at high risk for importation because of their proximity to a country with an outbreak. The number of priority countries rose from 31 in 2018 to 40 in 2019 because of a substantial increase in the number of VDPV outbreaks† (2,4). In areas with low poliovirus immunity, VDPVs can circulate in the community and cause outbreaks of paralysis; these are known as circulating vaccine derived polioviruses (cVDPVs) (4). In 2019, only 25 (63%) of the 40 designated priority countries met AFP surveillance indicators nationally; subnational surveillance performance varied widely and indicated focal weaknesses. High quality, sensitive surveillance is important to ensure timely detection and response to cVDPV and WPV transmission.

Multicountry Analysis of Spectrum of Clinical Manifestations of Children <5 Years of Age Hospitalized with Diarrhea.

After introduction of rotavirus vaccine, other pathogens might become leading causes of hospitalizations for severe diarrhea among children <5 years of age. Our study in 33 hospitals in 7 countries found acute gastroenteritis accounted for most (84%) reported hospitalizations of children with diarrhea. Bloody and persistent diarrhea each accounted for <1%.

Progress Toward Poliovirus Containment Implementation - Worldwide, 2018-2019.

Among the three wild poliovirus (WPV) types, type 2 (WPV2) was declared eradicated globally by the Global Commission for the Certification of Poliomyelitis Eradication (GCC) in 2015. Subsequently, in 2016, a global withdrawal of Sabin type 2 oral poliovirus vaccine (OPV2) from routine use, through a synchronized switch from the trivalent formulation of oral poliovirus vaccine (tOPV, containing vaccine virus types 1, 2, and 3) to the bivalent form (bOPV, containing types 1 and 3), was implemented. WPV type 3 (WPV3), last detected in 2012 (1), will possibly be declared eradicated in late 2019.* To ensure that polioviruses are not reintroduced to the human population after eradication, World Health Organization (WHO) Member States committed in 2015 to containing all polioviruses in poliovirus-essential facilities (PEFs) that are certified to meet stringent containment criteria; implementation of containment activities began that year for facilities retaining type 2 polioviruses (PV2), including type 2 oral poliovirus vaccine (OPV) materials (2). As of August 1, 2019, 26 countries have nominated 74 PEFs to retain PV2 materials. Twenty-five of these countries have established national authorities for containment (NACs), which are institutions nominated by ministries of health or equivalent bodies to be responsible for poliovirus containment certification. All designated PEFs are required to be enrolled in the certification process by December 31, 2019 (3). When GCC certifies WPV3 eradication, WPV3 and vaccine-derived poliovirus (VDPV) type 3 materials will also be required to be contained, leading to a temporary increase in the number of designated PEFs. When safer alternatives to wild and OPV/Sabin strains that do not require containment conditions are available for diagnostic and serologic testing, the number of PEFs will decrease. Facilities continuing to work with polioviruses after global eradication must minimize the risk for reintroduction into communities by adopting effective biorisk management practices.

Characterisation of a rare, reassortant human G10P[14] rotavirus strain detected in Honduras.

BACKGROUND: Although first detected in animals, the rare rotavirus strain G10P[14] has been sporadically detected in humans in Slovenia, Thailand, United Kingdom and Australia among other countries. Earlier studies suggest that the strains found in humans resulted from interspecies transmission and reassortment between human and bovine rotavirus strains. OBJECTIVES: In this study, a G10P[14] rotavirus genotype detected in a human stool sample in Honduras during the 2010-2011 rotavirus season, from an unvaccinated 30-month old boy who reported at the hospital with severe diarrhea and vomiting, was characterised to determine the possible evolutionary origin of the rare strain. METHODS: For the sample detected as G10P[14], 10% suspension was prepared and used for RNA extraction and sequence independent amplification. The amplicons were sequenced by next-generation sequencing using the Illumina MiSeq 150 paired end method. The sequence reads were analysed using CLC Genomics Workbench 6.0 and phylogenetic trees were constructed using PhyML version 3.0. FINDINGS: The next generation sequencing and phylogenetic analyses of the 11-segmented genome of the G10P[14] strain allowed classification as G10-P[14]-I2-R2-C2-M2-A3-N2-T6-E2-H3. Six of the genes (VP1, VP2, VP3, VP6, NSP2 and NSP4) were DS-1-like. NSP1 and NSP5 were AU-1-like and NSP3 was T6, which suggests that multiple reassortment events occurred in the evolution of the strain. The phylogenetic analyses and genetic distance calculations showed that the VP7, VP4, VP6, VP1, VP3, NSP1, NSP3 and NSP4 genes clustered predominantly with bovine strains. NSP2 and VP2 genes were most closely related to simian and human strains, respectively, and NSP5 was most closely related to a rhesus strain. MAIN CONCLUSIONS: The genetic characterisation of the G10P[14] strain from Honduras suggests that its genome resulted from multiple reassortment events which were possibly mediated through interspecies transmissions.

The path towards polio eradication over 40 years of the Expanded Program on Immunization in the Americas.

This article synthesizes the important lessons learned from polio eradication in the Region of the Americas, including initial and more recent challenges and best practices, as well as particular factors surrounding attainment of this ambitious goal. Using documents, interviews, and country surveys, the authors describe and analyze the strategies and lessons learned during the 40 years of the Expanded Program on Immunization (1977 - 2017). Some major milestones and chxallenges specifically covered are: the Vaccine-derived Poliovirus (VDPV) outbreak in the Dominican Republic; the regional "mop-up operation;" poliovirus containment in essential facilities; the unprecedented introduction of inactivated polio vaccine (IPV); the synchronized switch from trivalent to bivalent OPV; and the countries' unfailing commitment to the cause.

En este artículo se sintetizan las importantes enseñanzas extraídas de la erradicación de la poliomielitis en la Región de las Américas. Se presta especial atención a los retos y las mejores prácticas que se abordaron en un principioy a los más recientes, así como a los factores particulares que han girado en torno al logro de esta meta de gran alcance. Por medio de documentos, entrevistas y encuestas nacionales, las autoras describen y analizan las estrategias y enseñanzas extraídas a lo largo de los 40 años del Programa Ampliado de Inmunización (1977­2017). Entre los hitos y retos más importantes que se abordan en el artículo se encuentran los siguientes: el brote del poliovirus derivado de la vacuna en la República Dominicana; la campaña de vacunación "de seguimiento" a nivel regional; la contención del poliovirus en las instalaciones esenciales; la introducción sin precedentes de la vacuna antipoliomielítica con virus inactivados (VPI); el cambio sincronizado de la vacuna antipoliomielítica oral trivalente por la vacuna antipoliomielítica oral bivalente (conocido como "el switch"); y el compromiso inquebrantable de los países con esta causa.

Este artigo sintetiza os principais ensinamentos da erradicação da poliomielite na Região das Américas, expondo as dificuldades enfrentadas ao início e em um período mais recente, as boas práticas e os fatores inerentes relacionados ao alcance desta meta ambiciosa. A partir de documentos, entrevistas e levantamentos nos países, os autores descrevem e analisam as estratégias empregadas e a experiência obtida ao longo dos 40 anos do Programa Ampliado de Imunização (1977­2017). Entre os marcos e os desafios importantes abordados estão: o surto por vírus da poliomielite derivado da vacina (VDPV) na República Dominicana, a operação regional de "acabamento", a contenção do poliovírus em laboratório, a introdução inédita da vacina contra poliomielite com vírus inativado (VPI), a transição sincronizada da vacina oral contra poliomielite trivalente à bivalente e o firme compromisso dos países com a causa.

Human respiratory syncytial virus and metapneumovirus in patients with acute respiratory infection in Colombia, 2000 - 2011.

OBJECTIVE: To describe the epidemiology of respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) in Colombia from 2000 - 2011, including seasonal trends. METHODS: Nasopharyngeal aspirates and/or throat swabs from 14 870 patients with acute respiratory infections (ARI) were studied. Two subgroups were analyzed using molecular biology techniques. The first consisted of 264 RSV indirect fluorescence assay (IFA)-positive samples, the second of 264 RSV IFA-negative samples. RSV and hMPV were detected using reverse transcription polymerase chain reaction (RT-PCR). RESULTS: 2 799 samples (18.8%) contained a respiratory virus. RSV was detected by IFA in 1 333 samples (8.9%). RSV was detected by RT-PCR in 192 samples from the RSV IFA-positive subgroup and in 25 samples from the RSV IFA-negative subgroup. hMPV was detected in eight samples from the RSV IFA-positive subgroup and in 11 samples from the RSV IFA-negative subgroup. Among the RSV infections, subtype A was dominant in two-year intervals, subtype B was dominant in one-year intervals. 85.3% of RSV and 74% of hMPV infections occurred in children younger than 5 years old. RSV and hMPV infections were associated with rainy seasons. Co-infection with RSV A and RSV B was detected in two patients. Five cases of co-infection with RSV and hMPV were detected. CONCLUSIONS: This report is the first to examine the epidemiology of ARIs in Colombia, with an emphasis on RSV and hMPV. The samples studied here were obtained over a 12-year period and represent all age groups and both genders.

Sustaining the Elimination of Measles, Rubella and Congenital Rubella Syndrome in the Americas, 2019-2023: From Challenges to Opportunities.

This report reviews national data from all Member States on measles, rubella, and congenital rubella syndrome (CRS) elimination in the Region of the Americas during 2019-2023. It includes an analysis of compliance with vaccination coverage, surveillance indicators, and measles outbreaks, as well as an analysis of the response capacity of the laboratory network and a country case study that meets all indicators. The sources of information were the integrated epidemiological surveillance system for measles and rubella of the Pan American Health Organization (PAHO)/World Health Organization (WHO) and the Joint Reporting Form (eJRF), among others. From 2020 to 2022, regional coverage with first (MMR-1) and second doses (MMR-2) decreased to rates below 90%. The regional suspected case notification rate was maintained above the minimum expected 2.0 suspect cases per 100,000 population, except in 2021. During 2019 to 2023, 18 countries experienced outbreaks, with two of the outbreaks resulting in re-established endemic transmission. In conclusion, two countries in the Americas have not maintained measles elimination, but by the end of 2023 no country showed endemic measles transmission. One of the countries that lost its certification of elimination in 2018 managed to be reverified in 2023; the other is pending reverification. All countries maintained rubella elimination. Despite these challenges, the sustainability of the elimination of these diseases remains a health priority in the Region.

Molecular epidemiology of enteroviruses from Guatemalan wastewater isolated from human lung fibroblasts.

The Global Specialized Polio Laboratory at CDC supports the Global Poliovirus Laboratory Network with environmental surveillance (ES) to detect the presence of vaccine strain polioviruses, vaccine-derived polioviruses, and wild polioviruses in high-risk countries. Environmental sampling provides valuable supplementary information, particularly in areas with gaps in surveillance of acute flaccid paralysis (AFP) mainly in children less than 15 years. In collaboration with Guatemala's National Health Laboratory (Laboratorio Nacional de Salud Guatemala), monthly sewage collections allowed screening enterovirus (EV) presence without incurring additional costs for sample collection, transport, or concentration. Murine recombinant fibroblast L-cells (L20B) and human rhabdomyosarcoma (RD) cells are used for the isolation of polioviruses following a standard detection algorithm. Though non-polio-Enteroviruses (NPEV) can be isolated, the algorithm is optimized for the detection of polioviruses. To explore if other EV's are present in sewage not found through standard methods, five additional cell lines were piloted in a small-scale experiment, and next-generation sequencing (NGS) was used for the identification of any EV types. Human lung fibroblast cells (HLF) were selected based on their ability to isolate EV-A genus. Sewage concentrates collected between 2020-2021 were isolated in HLF cells and any cytopathic effect positive isolates used for NGS. A large variety of EVs, including echoviruses 1, 3, 6, 7, 11, 13, 18, 19, 25, 29; coxsackievirus A13, B2, and B5, EV-C99, EVB, and polioviruses (Sabin 1 and 3) were identified through genomic typing in NGS. When the EV genotypes were compared by phylogenetic analysis, it showed many EV's were genomically like viruses previously isolated from ES collected in Haiti. Enterovirus occurrence did not follow a seasonality, but more diverse EV types were found in ES collection sites with lower populations. Using the additional cell line in the existing poliovirus ES algorithm may add value by providing data about EV circulation, without additional sample collection or processing. Next-generation sequencing closed gaps in knowledge providing molecular epidemiological information on multiple EV types and full genome sequences of EVs present in wastewater in Guatemala.

Evaluation of the World Health Organization Global Invasive Bacterial Vaccine-Preventable Disease (IB-VPD) Surveillance Network's Laboratory External Quality Assessment Programme, 2014-2019.

Introduction. In 2009, the World Health Organization (WHO) established the Global Invasive Bacterial Vaccine Preventable Disease (IB-VPD) Surveillance Network (GISN) to monitor the global burden and aetiology of bacterial meningitis, pneumonia and sepsis caused by Haemophilus influenzae (Hi), Neisseria meningitidis (Nm) and Streptococcus pneumoniae (Sp).Hypothesis/Gap Statement. The GISN established an external quality assessment (EQA) programme for the characterization of Hi, Nm and Sp by culture and diagnostic PCR.Aim. To assess the performance of sentinel site laboratories (SSLs), national laboratories (NLs) and regional reference laboratories (RRLs) between 2014 and 2019 in the EQA programme.Methodology. Test samples consisted of bacterial smears for Gram-staining, viable isolates for identification and serotyping or serogrouping (ST/SG), plus simulated cerebrospinal fluid (CSF) samples for species detection and ST/SG by PCR. SSLs and NLs were only required to analyse the slides for Gram staining and identify the species of the live isolates. RRLs, and any SLs and NLs that had the additional laboratory capacity, were also required to ST/SG the viable isolates and analyse the simulated CSF samples.Results. Across the period, 69-112 SS/NL labs and eight or nine RRLs participated in the EQA exercise. Most participants correctly identified Nm and Sp in Gram-stained smears but were less successful with Hi and other species. SSLs/NLs identified the Hi, Nm and Sp cultures well and also submitted up to 56 % of Hi, 62 % of Nm and 33 % of Sp optional ST/SG results each year. There was an increasing trend in the proportion of correct results submitted over the 6 years for Nm and Sp. Some SSLs/NLs also performed the optional detection and ST/SG of the three organisms by PCR in simulated CSF from 2015 onwards; 89-100 % of the CSF samples were correctly identified and 76-93 % of Hi-, 90-100 % of Nm- and 75-100 % of Sp-positive samples were also correctly ST/SG across the distributions. The RRLs performed all parts of the EQA to a very high standard, with very few errors across all aspects of the EQA.Conclusion. The EQA has been an important tool in maintaining high standards of laboratory testing and building of laboratory capacity in the GISN.

Wastewater-based epidemiology for preventing outbreaks and epidemics in Latin America - Lessons from the past and a look to the future.

Wastewater-based epidemiology (WBE) is an approach with the potential to complement clinical surveillance systems. Using WBE, it is possible to carry out an early warning of a possible outbreak, monitor spatial and temporal trends of infectious diseases, produce real-time results and generate representative epidemiological information in a territory, especially in areas of social vulnerability. Despite the historical uses of this approach, particularly in the Global Polio Eradication Initiative, and for other pathogens, it was during the COVID-19 pandemic that occurred an exponential increase in environmental surveillance programs for SARS-CoV-2 in wastewater, with many experiences and developments in the field of public health using data for decision making and prioritizing actions to control the pandemic. In Latin America, WBE was applied in heterogeneous contexts and with emphasis on populations that present many socio-environmental inequalities, a condition shared by all Latin American countries. This manuscript addresses the concepts and applications of WBE in public health actions, as well as different experiences in Latin American countries, and discusses a model to implement this surveillance system at the local or national level. We emphasize the need to implement this sentinel surveillance system in countries that want to detect the early entry and spread of new pathogens and monitor outbreaks or epidemics of infectious agents in their territories as a complement of public health surveillance systems.

The effectiveness of COVID-19 vaccines in Latin America, 2021: a multicenter regional case-control study.

Background: As of September 2022, nearly 1.3 billion doses of COVID-19 vaccine products have been administered in Latin America and the Caribbean, where 27% of global COVID-19 deaths have occurred. This study aimed to estimate the effectiveness of COVID-19 vaccines against lab-confirmed COVID-19 related hospitalizations and deaths among adults in Argentina, Brazil, Chile, and Colombia. Methods: Using a test-negative case control design, we evaluated the effectiveness of a primary vaccination series considering six COVID-19 vaccine products (Sputnik V, mRNA-1273, CoronaVac, ChAdOx1, BNT162b2, Ad26.COV2.S) against lab-confirmed COVID-19 hospitalizations and deaths among 83,708 hospitalized adults from February-December, 2021. Data from hospitalization records, COVID surveillance, and vaccination registries were used. Vaccine effectiveness was estimated using logistic regression ((1-OR) x 100). Findings: The average age of participants was 56.7 (SD = 17.5), and 45,894 (54.8%) were male. Adjusted VE (aVE) estimates for full vaccination against hospitalization were 82% for mRNA-1273 (95% confidence interval (CI) = -30 to 98%), 76% (71%-81%) for BNT162b2, 65% (61-68%) for ChAdOx1, 57% (10-79%) for Sputnik V, 53% (50-56%) for CoronaVac, and 46% (23-62%) for Ad26.COV2.S. Estimates, particularly for CoronaVac, varied by variant. Decreasing aVE was estimated as age increased, particularly for CoronaVac and ChAdOx1. aVE estimates against death were generally higher, with 100% (CI not estimated) for mRNA-1273, 82% (69-90%) for BNT162b2, 73% (69-77%) for ChAdOx1, 65% (60-67%) for CoronaVac, 38% (-75 to 78%) for Sputnik V, 6% (-58 to 44%) for Ad26.COV2.S. Interpretation: Primary series vaccination with available COVID-19 vaccine products was effective against COVID-19 hospitalization and mortality. Effectiveness varied by product and declined with increasing age. Funding: This study was funded by the Pan-American Health Organization (PAHO, World Health Organization (WHO)). PAHO convened and led the study implementation.

Rotavirus genotypes in children under five years hospitalized with diarrhea in low and middle-income countries: Results from the WHO-coordinated Global Rotavirus Surveillance Network.

Rotavirus is the most common pathogen causing pediatric diarrhea and an important cause of morbidity and mortality in low- and middle-income countries. Previous evidence suggests that the introduction of rotavirus vaccines in national immunization schedules resulted in dramatic declines in disease burden but may also be changing the rotavirus genetic landscape and driving the emergence of new genotypes. We report genotype data of more than 16,000 rotavirus isolates from 40 countries participating in the Global Rotavirus Surveillance Network. Data from a convenience sample of children under five years of age hospitalized with acute watery diarrhea who tested positive for rotavirus were included. Country results were weighted by their estimated rotavirus disease burden to estimate regional genotype distributions. Globally, the most frequent genotypes identified after weighting were G1P[8] (31%), G1P[6] (8%) and G3P[8] (8%). Genotypes varied across WHO Regions and between countries that had and had not introduced rotavirus vaccine. G1P[8] was less frequent among African (36 vs 20%) and European (33 vs 8%) countries that had introduced rotavirus vaccines as compared to countries that had not introduced. Our results describe differences in the distribution of the most common rotavirus genotypes in children with diarrhea in low- and middle-income countries. G1P[8] was less frequent in countries that had introduced the rotavirus vaccine while different strains are emerging or re-emerging in different regions.

[Absence of poliovirus circulation in Colombian departments with vaccination coverage below 80%]. / Ausencia de circulación de poliovirus en departamentos colombianos con coberturas vacunales inferiores a 80%

This study aims to explore a possible silent circulation of wild and vaccine-derived polioviruses in departments of Colombia with polio vaccination coverage of below 80%. The study collected 52 samples of wastewater concentrated as a result of precipitation with polyethylene glycol and sodium chloride. The viral detection was carried out through isolation and the identification through neutralization of the cytopathic effect, as well as through a conventional polymerase chain reaction following reverse transcription. The isolated polioviruses were characterized by the VP1 gene sequence. In two of the 52 samples, there was a presence of the Sabin type 2 poliovirus with more than 99% sequence similarity with the Sabin type 2 strain polio. Circulation of the nonpolio enterovirus was detected in 17.3% of the samples. The serotypes identified corresponded to coxsackievirus B1, echovirus 30, and echovirus 11. No evidence of the spread of either vaccine-derived poliovirus or wild poliovirus was detected in the departments of Colombia with polio coverage lower than 80%.

Genome Sequences of 16 Enterovirus Isolates from Environmental Sewage in Guatemala, 2019 to 2021.

Enteroviruses can cause human infectious disease. We report 16 near-complete genome sequences of enteroviruses that were isolated through environmental surveillance of wastewater in Guatemala.

Achieving high immunogenicity against poliovirus with fractional doses of inactivated poliovirus vaccine in Ecuador-results from a cross-sectional serological survey.

Background: In January 2018, Ecuador changed its routine immunization schedule by replacing one full dose of inactivated poliovirus vaccine (IPV) administered intramuscularly at 2 months of age with two doses of fractional IPV (1/5th of full dose, fIPV) administered intradermally at 2 and 4 months of age; and bivalent oral poliovirus vaccine (serotypes 1 and 3, bOPV) continues to be used. We compared seroprevalence and titres of polio antibodies achieved by the past and the current immunization schedules. Methods: This was a cross-sectional serological survey in children in Ecuador who received bOPV and either one IPV dose in 2017 or two fIPV doses in 2018. One blood sample was collected between October 2020 and March 2021 and analysed for presence of poliovirus neutralizing antibodies at CDC, Atlanta by microneutralization assay. Findings: We obtained 321 analysable samples from 329 (97·6%) enrolled children (160 received IPV and 161 fIPV). For serotype 2, seroprevalence was 50·0% (CI95%= 44·2-55·8%) for IPV and 83·2% (CI95%=78·5-87·1%) for fIPV recipients (p<0·001). Median antibody titers for serotype 2 were significantly lower for IPV than for fIPV recipients (3·0, CI95%= 3 - 3·5 vs. 4·8, CI95%= 4·5 - 5·2, p<0·001). Seroprevalence for serotypes 1 and 3 was above 90% and was not significantly different between IPV and fIPV recipients. Interpretation: Ecuador achieved significantly better poliovirus serotype 2 immunogenicity with two fIPV doses than with one IPV dose, while preserving vaccine supply and reducing costs. Our data provide further evidence that fIPV is a beneficial and potentially a cost-effective option in polio immunization. Funding: WHO obtained funds for the study from Rotary International.