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.

Immune response to co-administration of measles, mumps, and rubella (MMR), and yellow fever vaccines: a randomized non-inferiority trial among one-year-old children in Argentina.

BACKGROUND: In yellow fever (YF) endemic areas, measles, mumps, and rubella (MMR), and YF vaccines are often co-administered in childhood vaccination schedules. Because these are live vaccines, we assessed potential immune interference that could result from co-administration. METHODS: We conducted an open-label, randomized non-inferiority trial among healthy 1-year-olds in Misiones Province, Argentina. Children were randomized to one of three groups (1:1:1): Co-administration of MMR and YF vaccines (MMR1YF1), MMR followed by YF vaccine four weeks later (MMR1YF2), or YF followed by MMR vaccine four weeks later (YF1MMR2). Blood samples obtained pre-vaccination and 28 days post-vaccination were tested for immunoglobulin G antibodies against measles, mumps, and rubella, and for YF virus-specific neutralizing antibodies. Non-inferiority in seroconversion was assessed using a -5% non-inferiority margin. Antibody concentrations were compared with Kruskal-Wallis tests. RESULTS: Of 851 randomized children, 738 were correctly vaccinated, had ≥ 1 follow-up sample, and were included in the intention-to-treat population. Non-inferior seroconversion was observed for all antigens (measles seroconversion: 97.9% in the MMR1YF1 group versus 96.3% in the MMR1YF2 group, a difference of 1.6% [90% CI -1.5, 4.7]; rubella: 97.9% MMR1YF1 versus 94.7% MMR1YF2, a difference of 3.3% [-0.1, 6.7]; mumps: 96.7% MMR1YF1 versus 97.9% MMR1YF2, a difference of -1.3% [-4.1, 1.5]; and YF: 96.3% MMR1YF1 versus 97.5% YF1MMR2, a difference of -1.2% [-4.2, 1.7]). Rubella antibody concentrations and YF titers were significantly lower following co-administration; measles and mumps concentrations were not impacted. CONCLUSION: Effective seroconversion was achieved and was not impacted by the co-administration, although antibody levels for two antigens were lower. The impact of lower antibody levels needs to be weighed against missed opportunities for vaccination to determine optimal timing for MMR and YF vaccine administration. TRIAL REGISTRATION: The study was retrospectively registered in ClinicalTrials.gov (NCT03368495) on 11/12/2017.

Enablers and barriers of maternal and neonatal immunization programs in Latin America.

BACKGROUND: The Region of the Americas has a long history of implementing maternal and neonatal immunization (MNI) programs. Our study aimed to understand the state of MNI policies, strategies and implementation practices in Latin America (LA). METHODS: Study conducted in 5 middle-income countries: Argentina, Brazil, Honduras, Mexico and Peru. The methods included a desk review, interviews with national stakeholders and health care providers, focus groups with pregnant women and observations in health facilities. Enablers and barriers were identified and categorized as individual, societal or related to the health system. RESULTS: All 5 participating countries had similar MNI policies and high access to antenatal care. Key enablers were the high acceptability of vaccination during pregnancy, high-level of political will and a national legal framework ensuring free access to vaccines. At the health system level, implementation was facilitated by the existence of immunization advisory committees, a pooled vaccine procurement mechanism, complementary vaccine delivery strategies, conditional cash transfer to users and performance incentives to health facilities. The main programmatic barriers were the lack of adequate MNI information; limited coordination between antenatal and immunization services; inadequate supply, resources and infrastructure; high staff turnover; insufficient training for health care providers; and weak monitoring and reporting systems. CONCLUSION: Middle-income countries in LA have successfully implemented MNI programs and several enablers were identified. To overcome remaining barriers, there is a need to focus on improving the "immunization journey" for pregnant women through providing more clear and timely information to users and providers; removing barriers to access; ensuring adequate supply, human resources and infrastructure; making the health service experience positive; and establishing integrated information systems that allow for monitoring the progress toward achieving MNI goals. Strengthening the MNI programs can also improve equitable access to health services and prepare for the introduction of future vaccines for pregnant women.

[Antipoliomyelitic vaccination in children living in Buenos Aires City]. / Vacunación antipoliomielítica en niños de la Ciudad de Buenos Aires.

Following the presentation of a confirmed case of paralytic polio Sabin-derived virus (VSD) in a child of 15 months we analyzed the coverage of poliomyelitis vaccination in children living in the City of Buenos Aires, in the 2006/2008 triennium. There was an improvement over the period analyzed, but values above 95% were reached only for the first dose. The proportion of inactivated vaccine (IPV) increased at the expense of live oral vaccine (OPV); in 2008, the first dose IPV coverage was 37.64% and 19.48% for the school entrance. The lack of intestinal immunity that occurs in children immunized with IPV, plus a poor coverage with OPV, allows the circulation of wild virus or VSD favoring the occurrence of paralytic poliomyelitis in unvaccinated or immunocompromised children.

Vacunación antipoliomielítica en niños de la Ciudad de Buenos Aires / Antipoliomyelitic vaccination in children living in Buenos Aires City

A raíz de la presentación de un caso confirmado de poliomielitis paralítica por virus Sabin derivado (VSD) en niños de 15 meses se analizó la cobertura de vacunación antipoliomielítica en niños residentes en la Ciudad de Buenos Aires, durante el trienio 2006/2008. Se observó una mejora a lo largo del período analizado, pero sólo hubo valores superiores al 95 por ciento para la primera dosis. Aumentó la proporción de vacuna inactivada (IPV) en desmedro de la vacuna oral viva (OPV); en 2008, la cobertura con IPV primera dosis fue del 37,64 por ciento y del 19,48 por ciento para el ingreso escolar. La falta de inmunidad intestinal que se presenta en los niños vacunados con IPV, asociada a coberturas insatisfactorias condiciona un terreno propicio para la circulación de virus salvaje o VSD, lo cual favorece la aparición de casos de poliomielitis paralítica en niños no vacunados o inmunodeficientes.

Patrón de ingesta de vegetales y frutas en adolescentes en el área metropolitana de Buenos Aires / Patterns of the intake of vegetables and fruits adolescents of the Metropolitan Distric of Buenos Aires

Introducción. La ingesta de menos de cinco raciones diarias de vegetales y frutas muestra una relación inversa con la posibilidad de padecer algunas patologías crónicas como cánceres digestivos y hormonodependientes o patologías cardiovasculares. En nuestro país existe escasa información sobre el consumo de vegetales y frutas. Objetivo. El presente estudio está dirigido a conocer la ingesta en una población de adolescentes de la región metropolitana de Buenos Aires. Población, material y métodos. Estudio observacional, descriptivo y transversal, con una muestra por conveniencia, aleatorizada y estratificada por edad. Se utilizó una encuesta que fue tomada por cada médico participante. Se incluyeron pacientes sanos de 10 a 18años, de ambos sexos que concurrieron para controles de salud, entre el 1 de octubre de 2000 al 31 de agosto de 2001. Se excluyeron pacientes con dietas especiales durante el último mes previo a la respuesta de la encuesta. Se trabajó con medidas de tendencia central y de dispersión y los resultados se expresaron en porcentajes. Resultados. En un modelo de encuesta sobre ingesta de24 horas del día anterior, se observó una pobre ingesta en los 520 encuestados, donde casi el 70 por ciento no ingirió porción alguna de vegetales y frutas, alrededor del 28 por ciento sólo una o dos porciones/día y apenas el 1 por ciento, cinco o más porciones/día. No se encontraron diferencias estadísticamente significativas en relación con el sexo, la edad y el lugar de atención (hospital público, obra social, consultorio privado). Conclusión. Ante estos resultados, sería útil desarrollar nuevos estudios epidemiológicos y proponer programas destinados a mejorar la información y consumo de estos alimentos en nuestra población.