Status of the national immunization technical advisory groups in the Americas: recommendations for improvement.

Objectives: To evaluate the structure and operation of national immunization technical advisory groups (NITAGs) in Latin America and the Caribbean and to make recommendations for improvement. Methods: A convenience sample of six current and eight former NITAG members representing 12 countries in the region were invited in 2022 to answer a web-based questionnaire on NITAG structure, organization, and procedures. The questionnaire used indicators similar to those in the Joint Reporting Form on Immunization. Participants were also asked about the role their NITAGs played in coronavirus disease 2019 (COVID-19) immunization policies. Results: Brazil, Dominican Republic, and Venezuela (Bolivarian Republic of) reported not having an active NITAG. The nine active NITAGs are structured and organized according to World Health Organization and Pan American Health Organization recommendations, with variations between countries. Most NITAGs include representatives of the five recommended medical specialties with the participation of additional members possible. Only Bolivia (Plurinational State of) and Mexico have no explicit policy for managing members' potential conflicts of interest. All NITAGs have an exclusively technical advisory role and generally meet once a quarter. Usually, NITAGs are asked by health ministries to analyze issues and make recommendations. All NITAGs, except for Peru's, actively participated in supporting decision-making for immunization policy on COVID-19. Conclusions: NITAGs have successfully supported vaccine policy-making through evidence-based recommendations. However, improvement in their structure, operation, and transparency is needed to help them keep up with the rapidly evolving field of immunization. Research on the impact of NITAGs is important to support the development of recommendations for improvement.

Status of the national immunization technical advisory groups in the Americas: recommendations for improvement / Estado actual de los grupos técnicos asesores nacionales sobre inmunización en la Región de las Américas: recomendaciones para su mejora / Situação dos Grupos Técnicos Assessores Nacionais sobre Imunização na Região das Américas: recomendações para melhorias

[ABSTRACT]. Objectives. To evaluate the structure and operation of national immunization technical advisory groups (NITAGs) in Latin America and the Caribbean and to make recommendations for improvement. Methods. A convenience sample of six current and eight former NITAG members representing 12 countries in the region were invited in 2022 to answer a web-based questionnaire on NITAG structure, organization, and procedures. The questionnaire used indicators similar to those in the Joint Reporting Form on Immunization. Participants were also asked about the role their NITAGs played in coronavirus disease 2019 (COVID-19) immunization policies. Results. Brazil, Dominican Republic, and Venezuela (Bolivarian Republic of) reported not having an active NITAG. The nine active NITAGs are structured and organized according to World Health Organization and Pan American Health Organization recommendations, with variations between countries. Most NITAGs include representatives of the five recommended medical specialties with the participation of additional members possible. Only Bolivia (Plurinational State of) and Mexico have no explicit policy for managing members’ potential conflicts of interest. All NITAGs have an exclusively technical advisory role and generally meet once a quarter. Usually, NITAGs are asked by health ministries to analyze issues and make recommendations. All NITAGs, except for Peru’s, actively participated in supporting decision-making for immunization policy on COVID-19. Conclusions. NITAGs have successfully supported vaccine policy-making through evidence-based recommendations. However, improvement in their structure, operation, and transparency is needed to help them keep up with the rapidly evolving field of immunization. Research on the impact of NITAGs is important to support the development of recommendations for improvement.

[RESUMEN]. Objetivos. Evaluar la estructura y el funcionamiento de los grupos técnicos asesores nacionales sobre inmunización (NITAG, por su sigla en inglés) en América Latina y el Caribe y formular recomendaciones para su mejora. Métodos. En el 2022, se seleccionó una muestra por conveniencia, formada por seis miembros actuales y ocho antiguos miembros de NITAG que representaban a 12 países de la Región, y se les invitó a responder un cuestionario en línea sobre la estructura, la organización y los procedimientos de los NITAG. El cuestionario utilizaba indicadores similares a los del formulario de notificación conjunta de datos sobre inmunización. También se preguntó a los participantes sobre el papel que desempeñaron sus NITAG en las políticas de inmunización contra la COVID-19. Resultados. Brasil, República Dominicana y Venezuela (República Bolivariana de) informaron que no tenían un NITAG activo. Los nueve NITAG activos están estructurados y organizados según las recomendaciones de la Organización Mundial de la Salud y la Organización Panamericana de la Salud, con diferencias entre los países. La mayoría de los NITAG cuentan con representantes de las cinco especialidades médicas recomendadas, con la posibilidad de participación de miembros adicionales. Solo Bolivia (Estado Plurinacional de) y México carecen de una política explícita para gestionar los posibles conflictos de intereses de los miembros. Todos los NITAG tienen una función exclusivamente de asesoramiento técnico y suelen reunirse en forma trimestral. Por lo general, los ministerios de salud les solicitan el análisis de problemas y la formulación de recomendaciones. Salvo en el caso de Perú, todos los NITAG participaron activamente en la facilitación de la toma de decisiones sobre políticas de inmunización contra la COVID-19. Conclusiones. Los NITAG han brindado apoyo con éxito a la formulación de políticas de vacunación mediante recomendaciones basadas en la evidencia. Sin embargo, es necesario mejorar su estructura, funcionamiento y transparencia para que puedan mantenerse al día en el campo de la inmunización en constante evolución. La investigación sobre el impacto de los NITAG es importante para respaldar la formulación de recomendaciones para su mejora.

[RESUMO]. Objetivos. Avaliar a estrutura e o funcionamento dos Grupos Técnicos Assessores Nacionais sobre Imunização (NITAGs, na sigla em inglês) na América Latina e no Caribe e fazer recomendações para melhorá-los. Métodos. Em 2022, uma amostra de conveniência de seis membros atuais e oito ex-membros de NITAGs, representando 12 países da Região, foi convidada a responder a um questionário on-line sobre a estrutura, a organização e os procedimentos dos NITAGs. O questionário usou indicadores semelhantes aos do formulário de notificação conjunta sobre imunização. Também se perguntou aos participantes sobre o papel que seus NITAGs haviam desempenhado nas políticas de imunização contra a doença pelo coronavírus 2019 (COVID-19). Resultados. O Brasil, a República Dominicana e a Venezuela (República Bolivariana da) informaram não ter um NITAG ativo. Os nove NITAGs ativos são estruturados e organizados de acordo com as recomendações da Organização Mundial da Saúde e da Organização Pan-Americana da Saúde, com variações entre os países. A maioria dos NITAGs inclui representantes das cinco especialidades médicas recomendadas, sendo possível a participação de outros membros. Somente a Bolívia (Estado Plurinacional da) e o México não têm uma política explícita para gerenciar possíveis conflitos de interesse dos membros. Todos os NITAGs têm uma função exclusiva de assessoria técnica e geralmente se reúnem trimestralmente. Normalmente, os ministérios da Saúde solicitam aos NITAGs que analisem problemas e façam recomendações. Todos os NITAGs, exceto o do Peru, participaram ativamente no apoio ao processo decisório da política de imunização contra a COVID-19. Conclusões. Os NITAGs conseguiram apoiar a formulação de políticas de vacinação por meio de recomendações baseadas em evidências. Entretanto, é necessário melhorar a estrutura, o funcionamento e a transparência dos NITAGs para ajudá-los a se manter em dia com o campo da imunização, que está evoluindo rapidamente. A pesquisa sobre o impacto dos NITAGs é importante para apoiar a elaboração de recomendações de melhoria.

Spectral norm and energy of a digraph with respect to a VDB topological index.

The set of singular values of a digraph with respect to a vertex-degree based topological index is the set of all singular values of its general adjacency matrix. The spectral norm is the largest singular value and the energy the sum of the singular values. In this paper we characterize the digraphs which have exactly one singular value different from zero and the digraphs for which all singular values are equal. As a consequence, we deduce sharp upper and lower bounds for the spectral norm and energy of digraphs. In addition to being a natural generalization, proving the results in the general setting of digraphs allows us to deduce new results on graph energy.

Strategies for expanding childhood vaccination in the Americas following the COVID-19 pandemic.

Objective: To provide an overview of the status of the childhood vaccination schedule in the Americas, outline program structures, and identify updated implementation strategies to improve vaccination coverage following the COVID-19 pandemic. Methods: A group of experts in pediatrics, epidemiology, vaccines, and global and public health discussed the current status of the childhood vaccination schedule in the Americas, describing the program structure and identifying new implementation strategies that have the potential to improve vaccination coverage in the post-pandemic context, after the challenges COVID-19 presented for more than two years. Results: The Americas currently face a high risk of resurgence of diseases that were previously controlled or eliminated. Therefore, it is important to find new strategies to educate citizens on the risks associated with lower vaccination rates, especially in children. Conclusions: New strategies along with strong mobilization of the population and advocacy by citizens are necessary to prevent antivaccination groups from gaining a stronger presence in the region and jeopardizing the credibility of the Expanded Program on Immunization.

Strategies for expanding childhood vaccination in the Americas following the COVID-19 pandemic / Estrategias para ampliar la vacunación infantil en la Región de las Américas después de la pandemia de COVID-19 / Estratégias para ampliar a vacinação infantil nas Américas depois da pandemia de COVID-19

[ABSTRACT]. Objective. To provide an overview of the status of the childhood vaccination schedule in the Americas, outline program structures, and identify updated implementation strategies to improve vaccination coverage following the COVID-19 pandemic. Methods. A group of experts in pediatrics, epidemiology, vaccines, and global and public health discussed the current status of the childhood vaccination schedule in the Americas, describing the program structure and identifying new implementation strategies that have the potential to improve vaccination coverage in the post-pandemic context, after the challenges COVID-19 presented for more than two years. Results. The Americas currently face a high risk of resurgence of diseases that were previously controlled or eliminated. Therefore, it is important to find new strategies to educate citizens on the risks associated with lower vaccination rates, especially in children. Conclusions. New strategies along with strong mobilization of the population and advocacy by citizens are necessary to prevent antivaccination groups from gaining a stronger presence in the region and jeopardizing the credibility of the Expanded Program on Immunization.

[RESUMEN]. Objetivo. Presentar un panorama general de la situación del calendario de vacunación infantil en la Región de las Américas, describir la estructura de los programas y encontrar estrategias actualizadas para su ejecución a fin de mejorar la cobertura de vacunación después de la pandemia de COVID-19. Métodos. Un grupo de expertos en pediatría, epidemiología, vacunas y salud pública y mundial analizó la situación actual del calendario de vacunación infantil en la Región de las Américas, mediante la descripción de la estructura de los programas y la búsqueda de nuevas estrategias de ejecución capaces de mejorar la cobertura de vacunación en el contexto posterior a la pandemia de COVID-19, una vez superados los desafíos planteados por esta durante más de dos años. Resultados. En este momento, en la Región de las Américas hay un riesgo alto de reaparición de enferme- dades previamente controladas o eliminadas. En consecuencia, es importante contar con nuevas estrategias para la educación de salud de la ciudadanía sobre los riesgos asociados a las tasas bajas de vacunación, especialmente en la población infantil. Conclusiones. Es necesario contar con nuevas estrategias, acompañadas de una fuerte movilización de la población y una promoción por parte de la ciudadanía, para evitar que los grupos que generan mensajes antivacunas aumenten su presencia en la Región y pongan en peligro la credibilidad del Programa Ampliado de Inmunización.

[RESUMO]. Objetivo. Apresentar um panorama da situação do calendário de vacinação infantil nas Américas, definir a estrutura do programa e identificar estratégias de implementação atualizadas para melhorar a cobertura vacinal depois da pandemia de COVID-19. Métodos. Um grupo de especialistas em pediatria, epidemiologia, vacinas e saúde pública e global discutiu a situação atual do calendário de vacinação infantil nas Américas, descrevendo a estrutura dos programas e identificando novas estratégias de implementação que poderiam melhorar a cobertura vacinal no contexto pós-pandemia, na sequência dos desafios impostos pela COVID-19 durante mais de dois anos. Resultados. Atualmente, as Américas enfrentam um grande risco de ressurgimento de doenças já controla- das ou eliminadas. Desse modo, é importante identificar novas estratégias para conscientizar os cidadãos sobre os riscos decorrentes da queda das taxas de vacinação, sobretudo em crianças. Conclusões. É necessário adotar novas estratégias, aliadas a uma forte mobilização da população e pro- moção da causa pelos cidadãos, a fim de impedir que os grupos antivacinas fortaleçam sua presença na região e coloquem em risco a credibilidade do Programa Ampliado de Imunização.

Strategies for expanding childhood vaccination in the Americas following the COVID-19 pandemic / Estrategias para ampliar la vacunación infantil en la Región de las Américas después de la pandemia de COVID-19 / Estratégias para ampliar a vacinação infantil nas Américas depois da pandemia de COVID-19

ABSTRACT Objective. To provide an overview of the status of the childhood vaccination schedule in the Americas, outline program structures, and identify updated implementation strategies to improve vaccination coverage following the COVID-19 pandemic. Methods. A group of experts in pediatrics, epidemiology, vaccines, and global and public health discussed the current status of the childhood vaccination schedule in the Americas, describing the program structure and identifying new implementation strategies that have the potential to improve vaccination coverage in the post-pandemic context, after the challenges COVID-19 presented for more than two years. Results. The Americas currently face a high risk of resurgence of diseases that were previously controlled or eliminated. Therefore, it is important to find new strategies to educate citizens on the risks associated with lower vaccination rates, especially in children. Conclusions. New strategies along with strong mobilization of the population and advocacy by citizens are necessary to prevent antivaccination groups from gaining a stronger presence in the region and jeopardizing the credibility of the Expanded Program on Immunization.

RESUMEN Objetivo. Presentar un panorama general de la situación del calendario de vacunación infantil en la Región de las Américas, describir la estructura de los programas y encontrar estrategias actualizadas para su ejecución a fin de mejorar la cobertura de vacunación después de la pandemia de COVID-19. Métodos. Un grupo de expertos en pediatría, epidemiología, vacunas y salud pública y mundial analizó la situación actual del calendario de vacunación infantil en la Región de las Américas, mediante la descripción de la estructura de los programas y la búsqueda de nuevas estrategias de ejecución capaces de mejorar la cobertura de vacunación en el contexto posterior a la pandemia de COVID-19, una vez superados los desafíos planteados por esta durante más de dos años. Resultados. En este momento, en la Región de las Américas hay un riesgo alto de reaparición de enfermedades previamente controladas o eliminadas. En consecuencia, es importante contar con nuevas estrategias para la educación de salud de la ciudadanía sobre los riesgos asociados a las tasas bajas de vacunación, especialmente en la población infantil. Conclusiones. Es necesario contar con nuevas estrategias, acompañadas de una fuerte movilización de la población y una promoción por parte de la ciudadanía, para evitar que los grupos que generan mensajes antivacunas aumenten su presencia en la Región y pongan en peligro la credibilidad del Programa Ampliado de Inmunización.

RESUMO Objetivo. Apresentar um panorama da situação do calendário de vacinação infantil nas Américas, definir a estrutura do programa e identificar estratégias de implementação atualizadas para melhorar a cobertura vacinal depois da pandemia de COVID-19. Métodos. Um grupo de especialistas em pediatria, epidemiologia, vacinas e saúde pública e global discutiu a situação atual do calendário de vacinação infantil nas Américas, descrevendo a estrutura dos programas e identificando novas estratégias de implementação que poderiam melhorar a cobertura vacinal no contexto pós-pandemia, na sequência dos desafios impostos pela COVID-19 durante mais de dois anos. Resultados. Atualmente, as Américas enfrentam um grande risco de ressurgimento de doenças já controladas ou eliminadas. Desse modo, é importante identificar novas estratégias para conscientizar os cidadãos sobre os riscos decorrentes da queda das taxas de vacinação, sobretudo em crianças. Conclusões. É necessário adotar novas estratégias, aliadas a uma forte mobilização da população e promoção da causa pelos cidadãos, a fim de impedir que os grupos antivacinas fortaleçam sua presença na região e coloquem em risco a credibilidade do Programa Ampliado de Imunização.

Are the first 1,000 days of life a neglected vital period to prevent the impact on maternal and infant morbimortality of infectious diseases in Latin America? Proceedings of a workshop of experts from the Latin American Pediatric Infectious Diseases Society, SLIPE.

While the first 1,000 days of life are a critical period in child's development, limited information on the main determinants affecting this period in the Latin America and the Caribbean (LAC) region is available. Therefore, the Latin American Pediatric Infectious Diseases Society (SLIPE) held an ad hoc workshop in May 2022 with an expert panel designed to analyze the main factors impacting the development of childhood in the region during this period and the main causes of maternal infant morbimortality. The aim was to identify priorities, generate recommendations, and advise practical actions to improve this situation. Considerations were made about the challenges involved in bridging the gap that separates the region from more developed countries regarding an optimal early childhood and maternal care. Extensive discussion was conducted to reach consensus recommendations on general strategies intended to reduce maternal and infant mortality associated with infections and immune-preventable diseases during the first 1,000 days of life in LAC.

Improving Middle-Income Countries Access to Vaccines. A Blueprint to Overcome Current Challenges.

The Global Health Consortium at Florida International University developed an end-to-end solution framework based on the input of a diverse panel of experts from middle-income country (MIC) government agencies, public health think tanks, academia, and nonprofit organizations to identify mechanisms to help MIC governments and stakeholders increase access to novel vaccines for infectious diseases. The resultant layout can be deployed to improve vaccine discovery and development, strengthen regulatory processes, and boost vaccine production, access, and implementation. Mechanisms include policies and incentives MIC governments can use to stimulate vaccine investment and activity, as well as actions government agencies can take together with other stakeholders to coordinate efforts or build capabilities. Through a series of individual virtual interviews, we engaged diverse experts from MIC government agencies, public health think tanks, academia, and nonprofit organizations who understand the vaccine ecosystem, immunization policies, and population health financing at global, regional, and country levels. Responses were mapped, and in-depth questions were prepared for a group virtual discussion. This paper is the result of such a group discussion. The panel identified clear opportunities for MICs to improve locally-driven innovations and future access to novel vaccines. It proposes a solution framework for countries considering investing in vaccine research and development and innovation to use as a guide to evaluate the steps they could take to improve such an environment and incentivize innovation in vaccine development. It is hoped that this end-to-end solution framework will become a key resource to help MICs strengthen policies and take more actions to make such improvements.

Systematic Review and Meta-analysis of Deaths Attributable to Antimicrobial Resistance, Latin America.

Antimicrobial resistance is a pressing global health concern, leading to 4.95 million deaths in 2019. We conducted a systematic review and meta-analysis to assess the lethality attributed to infections caused by multidrug-resistant organisms (MDROs) in Latin America and the Caribbean. A comprehensive search of major databases retrieved relevant studies from 2000-2022. We included 54 observational studies, primarily from Brazil, Argentina, and Colombia. The most commonly studied organism was methicillin-resistant Staphylococcus aureus. The overall unadjusted case fatality rate related to MDROs was 45.0%; higher adjusted lethality was observed in persons infected with MDROs than in those infected with other pathogens (adjusted odds ratio 1.93, 95% CI 1.58-2.37). A higher lethality rate was seen in patients who did not receive appropriate empirical treatment (odds ratio 2.27, 95% CI 1.44-3.56). These findings underscore the increased lethality associated with antimicrobial resistance in Latin America and the Caribbean.

Microbial diversity across compartments in an aquaponic system and its connection to the nitrogen cycle.

Aquaponics combines hydroponic crop production with recirculating aquaculture. These systems comprise various compartments (fish tank, biofilter, sump, hydroponic table, radial flow settler and anaerobic digester), each with their own specific environmental pressures, which trigger the formation of unique microbial communities. Triplicated aquaponic systems were used to investigate the microbial community composition during three lettuce growing cycles. The sampling of individual compartments allowed community patterns to be generated using amplicon sequencing of bacterial and archaeal 16S rRNA genes. Nitrifying bacteria were identified in the hydroponic compartments, indicating that these compartments may play a larger role than previously thought in the system's nitrogen cycle. In addition to the observed temporal changes in community compositions within the anaerobic compartment, more archaeal reads were obtained from sludge samples than from the aerobic part of the system. Lower bacterial diversity was observed in fresh fish feces, where a highly discrete gut flora composition was seen. Finally, the most pronounced differences in microbial community compositions were observed between the aerobic and anaerobic loops of the system, with unique bacterial compositions in each individual compartment.

Obesity in Latin America, a scoping review of public health prevention strategies and an overview of their impact on obesity prevention.

OBJECTIVE: To describe the strategies implemented in seventeen Latin American countries for obesity prevention and to provide an overview of their impact. DESIGN: A thorough search of strategies and their impact was done through an Internet search, governmental webpages, reports and research articles in English, Spanish and Portuguese. SETTING: Latin America (not including the Caribbean countries). PARTICIPANTS: Any. RESULTS: The Ministry of Health is the main oversight for obesity prevention, with six countries having a specific structure for this. Regular obesity monitoring occurs in a few countries, and thirteen countries have a national obesity prevention plan. The main regulations being implemented/designed are front-of-package labelling (sixteen countries), school environment (fifteen countries), school nutrition education (nine countries), promotion of physical activity level (nine countries) and sugar-sweetened beverage tax (eight countries). All countries have dietary guidelines. The main community-based programmes being implemented are school meals (seventeen countries), complementary nutrition (eleven countries), nutrition education (fourteen countries), promotion of physical activity (nine countries) and healthy environments (nine countries). Most of these strategies have not been evaluated. The few with positive results have used a coordinated, multi-disciplinary and multi-sector approach, with legislation and executive-level support. CONCLUSIONS: Important obesity prevention strategies are being implemented in the seventeen Latin American countries included in the present review. However, few have been evaluated to assess their impact on preventing obesity. This information can help assess that actions can be generalised to other countries within the region and can help inform how to prevent obesity in different settings.

Environmental parameters and microbial community profiles as indication towards microbial activities and diversity in aquaponic system compartments.

BACKGROUND: An aquaponic system couples cultivation of plants and fish in the same aqueous medium. The system consists of interconnected compartments for fish rearing and plant production, as well as for water filtration, with all compartments hosting diverse microbial communities, which interact within the system. Due to the design, function and operation mode of the individual compartments, each of them exhibits unique biotic and abiotic conditions. Elucidating how these conditions shape microbial communities is useful in understanding how these compartments may affect the quality of the water, in which plants and fish are cultured. RESULTS: We investigated the possible relationships between microbial communities from biofilms and water quality parameters in different compartments of the aquaponic system. Biofilm samples were analyzed by total community profiling for bacterial and archaeal communities. The results implied that the oxygen levels could largely explain the main differences in abiotic parameters and microbial communities in each compartment of the system. Aerobic system compartments are highly biodiverse and work mostly as a nitrifying biofilter, whereas biofilms in the anaerobic compartments contain a less diverse community. Finally, the part of the system connecting the aerobic and anaerobic processes showed common conditions where both aerobic and anaerobic processes were observed. CONCLUSION: Different predicted microbial activities for each compartment were found to be supported by the abiotic parameters, of which the oxygen saturation, total organic carbon and total nitrogen differentiated clearly between samples from the main aerobic loop and the anaerobic compartments. The latter was also confirmed using microbial community profile analysis.

Review: Type 2 diabetes in Latin America and the Caribbean: Regional and country comparison on prevalence, trends, costs and expanded prevention.

PURPOSE: To present an overview of type 2 diabetes status in Latin America and the Caribbean region. METHODS: The data were collected from the International Diabetes Federation Atlas and other available published sources where we identified the prevalence in Latin America and the Caribbean, the trends by regions, and sex. Also, we summarized the type 2 diabetes direct and indirect costs, and the current preventative programs and policies available for each region. RESULTS: Latin America and the Caribbean has one of the fastest-growing prevalence of type 2 diabetes, in particular the Caribbean region. Costs are relatively high in Central American countries and the Caribbean Islands. Currently, type 2 diabetes prevention, diagnosis, and management are insufficient in Latin America and the Caribbean and they do not offer a multidisciplinary integrative approach. CONCLUSION: Effective and preventive multidisciplinary policies should be implemented in Latin America and the Caribbean to decrease the high burden of type 2 diabetes.

The decline of dengue in the Americas in 2017: discussion of multiple hypotheses.

OBJECTIVE: Since the 1980s, dengue incidence has increased 30-fold. However, in 2017, there was a noticeable reduction in reported dengue incidence cases within the Americas, including severe and fatal cases. Understanding the mechanism underlying dengue's incidence and decline in the Americas is vital for public health planning. We aimed to provide plausible explanations for the decline in 2017. METHODS: An expert panel of representatives from scientific and academic institutions, Ministry of Health officials from Latin America and PAHO/WHO staff met in October 2017 to propose hypotheses. The meeting employed six moderated plenary discussions in which participants reviewed epidemiological evidence, suggested explanatory hypotheses, offered their expert opinions on each and developed a consensus. RESULTS: The expert group established that in 2017, there was a generalised decreased incidence, severity and number of deaths due to dengue in the Americas, accompanied by a reduction in reported cases of both Zika and chikungunya virus infections, with no change in distribution among age groups affected. This decline was determined to be unlikely due to changes in epidemiological surveillance systems, as similar designs of surveillance systems exist across the region. Although sudden surveillance disruption is possible at a country or regional level, it is unlikely to occur in all countries simultaneously. Retrospective modelling with epidemiological, immunological and entomological information is needed. Host or immunological factors may have influenced the decline in dengue cases at the population level through immunity; however, herd protection requires additional evidence. Uncertainty remains regarding the effect on the outcome of sequential infections of different dengue virus (DENV) types and Zika virus (ZIKV), and vice versa. Future studies were recommended that examine the epidemiological effect of prior DENV infection on Zika incidence and severity, the epidemiological effect of prior Zika virus infection on dengue incidence and severity, immune correlates based on new-generation ELISA assays, and impact of prior DENV/other arbovirus infection on ZIKV immune response in relation to number of infections and the duration of antibodies in relation to interval of protection. Follow-up studies should also investigate whether increased vector control intensification activities contributed to the decline in transmission of one or more of these arboviruses. Additionally, proposed studies should focus on the potential role of vector competence when simultaneously exposed to various arboviruses, and on entomological surveillance and its impact on circulating vector species, with a goal of applying specific measures that mitigate seasonal occurrence or outbreaks. CONCLUSIONS: Multifactorial events may have accounted for the decline in dengue seen in 2017. Differing elements might explain the reduction in dengue including elements of immunity, increased vector control, and even vector and\or viruses changes or adaptations. Most of the results of this expert consensus group meeting are hypothetical and based on limited evidence. Further studies are needed.

OBJECTIF: Depuis les années 1980, l'incidence de la dengue a été multipliée par 30. Cependant, en 2017, il y a eu une réduction notable du nombre de cas d'incidence de dengue rapportés dans les Amériques. Nous voulions fournir des explications plausibles à la baisse en 2017. MÉTHODES: Un groupe d'experts constitué de représentants d'institutions scientifiques et académiques, d'officiels des Ministères de la Santé d'Amérique Latine et de membres du personnel de l'OPS/OMS s'est réuni en octobre 2017 pour proposer et évaluer des hypothèses. RÉSULTATS: En 2017, il y a eu une baisse généralisée de l'incidence, de la sévérité et du nombre de décès dus à la dengue dans les Amériques, accompagnée d'une réduction des cas rapportés d'infections par le virus Zika et par le virus du chikungunya, sans modification dans la répartition entre les groupes d'âge affectés. Il a été déterminé que ce déclin était peu probablement dû aux changements dans les systèmes de surveillance épidémiologique, étant donné que des systèmes de surveillance similaires existaient dans toute la région. Bien que des perturbations soudaines dans la surveillance soient possibles au niveau national ou régional, il est peu probable que cela se produise simultanément dans tous les pays. Une modélisation rétrospective avec des informations épidémiologiques, immunologiques et entomologiques est nécessaire. Des facteurs liés à l'hôte ou immunologiques peuvent avoir influencé le déclin des cas de dengue au niveau de la population par le biais de l'immunité; cependant, l'évidence d'une protection conférée par l'effet du troupeau nécessite des données supplémentaires. Une incertitude subsiste quant à l'effet sur le résultat des infections séquentielles de différents types du virus de la dengue (DENV) et du virus Zika (ZIKV), et vice-versa. Les études à venir devraient examiner (1) l'effet épidémiologique d'une infection antérieure par le DENV sur l'incidence et la sévérité du virus Zika, (2) l'effet épidémiologique d'une infection antérieure par le virus Zika sur l'incidence et la sévérité de la dengue, (3) les corrélats immunitaires basés sur des tests ELISA de nouvelle génération, (4) l' impact d'une infection antérieure à DENV/autres arbovirus sur la réponse immunitaire au ZIKV en fonction du nombre d'infections et de la durée des anticorps en fonction de l'intervalle de protection, (5) si des activités d'intensification de la lutte antivectorielle ont contribué à la diminution de la transmission d'un ou plusieurs de ces arbovirus, (6) le rôle potentiel de la compétence vectorielle lorsqu'ils sont exposés simultanément à différents arbovirus, (7) la surveillance entomologique et son impact sur la circulation d'espèces de vecteurs, dans le but d'appliquer des mesures spécifiques qui réduisent l'occurrence saisonnière d'épidémies. CONCLUSIONS: Des événements multifactoriels pourraient expliquer le déclin observé de la dengue en 2017. La plupart des résultats de cette réunion du groupe de consensus d'experts sont hypothétiques, reposent sur des données limitées et requièrent des investigations supplémentaires.

Varicella epidemiology in Latin America and the Caribbean.

INTRODUCTION: The Latin American Society of Pediatric Infectious Diseases (SLIPE), with the support of the Americas Health Foundation (AHF), has developed a position paper on varicella prevention in Latin America and Caribbean countries (LAC). This article summarizes the most relevant aspects of varicella in LAC, and emphasizes the need to include the varicella vaccine in the national immunization programs in the Region and evaluate its impact disease burden. AREAS COVERED: A systematic review was conducted of the medical evidence published and presented at various regional medical conferences on the disease burden in LAC, the advances made by prevention programs, the available vaccines in the Region, and their immunogenicity, efficacy, effectiveness, and safety. The different national varicella-prevention vaccination programs were reviewed, as was available information regarding the impact of these programs on the epidemiology of varicella in those countries implementing a varicella vaccine strategy. Following that initial publication, an update was conducted, including data from additional countries in the Region. EXPERT COMMENTARY: Varicella is a vaccine-preventable infectious disease, considered a 'benign disease' because of lower complication rates when compared with measles, pertussis. The incorporation of a two-dose varicella vaccine in national immunization schedules in all countries throughout LAC would be of great benefit to the health of the children.

Seroprevalencia del virus de la hepatitis A en niños de 1 a 15 años en un hospital universitario / Seroprevalence of the hepatitis A virus in children from 1 to 15 years old in a university hospital

Introducción. La hepatitis A es una enfermedad infectocontagiosa causada por un virus ARN no encapsulado de la familia Picornaviridae y del género Hepatovirus, que se trasmite por vía fecal-oral, bien sea de persona a persona o en epidemias originadas por una fuente común. Objetivo. Se estimo la seroprevalencia de anticuerpos de tipo IgG contra el virus de la hepatitis A en niños de 1 a 15 años, atendidos en un hospital universitario, como parte de un estudio cooperativo nacional. Métodos. Se realizó un estudio descriptivo y prospectivo, entre junio y noviembre de 2007. Los niveles de anticuerpos se detectaron mediante un inmunoensayo enzimático de micropartículas. A cada participante del estudio se le hizo una encuesta de riesgo con las variables objeto del estudio. Resultados. Se estudiaron 422 niños. La prevalencia global de anticuerpos contra el virus de la hepatitis A fue de 29,1%: 37,1% en el grupo de 5 a 9 años, 36,1%, en el de 10 a 15 y 13,8%, en el de 1 a 4 años. La mayor proporción de prevalencia de anticuerpos se encontró en los niños de estrato socioeconómico más bajo: 44,2% para el estrato 1 y 27,9% para el estrato 2. Discusión. En este estudio se encontró una seroprevalencia de anticuerpos para hepatitis A más baja en menores de 5 años, lo que puede indicar una transición del patrón epidemiológico hacia un nivel intermedio. La prevalencia fue mayor en los niños de estratos socioeconómicos bajos, lo que puede estar en relación con el hacinamiento y las malas prácticas de higiene.

Introduction: Hepatitis A is an infectious disease caused by a non-encapsulated RNA virus of the Picornaviridae family, classified as Hepatovirus. It is transmitted by a fecal-oral route, either from person to person or in common source epidemics. Objective: The aim of this study was to estimate the seroprevalence of IgG antibodies against the hepatitis A virus in children aged 1-15 years, treated in a university hospital as part of a national collaborative study. Methods: A descriptive study was performed between June and November 2007. The antibody titers were detected by means of a Microparticle Capture Enzyme Immunoassay. A survey to identify risk factors was conducted for each participant, with additional variables under study. Results: We studied 422 children. The overall prevalence of antibodies against hepatitis A was 29.1%, with 37.1% in the group of 5 to 9 years of age, 36.1% for 10 to 15, and 13.8% for 1 to 4. The highest proportion of antibody prevalence was found in children of the lowest socioeconomic status, 44.2% for the stratum 1 and 27.9% for the stratum 2. Conclusion: The seroprevalence to hepatitis A virus was lower in children with less than five years of age, which is an indication of a transition of the epidemiological profile to an intermediate one. The prevalence was higher in children of low socioeconomic levels, which may be related to overcrowding and poor hygiene practices.