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.

Chronic medical conditions associated with invasive pneumococcal diseases in inpatients in teaching hospitals in São Paulo city: Estimating antimicrobial susceptibility and serotype-coverage of pneumococcal vaccines

ABSTRACT Background: Chronic conditions increase the risk of invasive pneumococcal diseases (IPD). Pneumococcal vaccination remarkably reduced IPD morbimortality in vulnerable populations. In Brazil, pneumococcal vaccines are included in the National Immunization Program (PNI): PCV10 for < 2 years-old, and PPV23 for high risk-patients aged ≥ 2 years and institutionalized ≥ 60 years. PCV13 is available in private clinics and recommended in the PNI for individuals with certain underlying conditions. Methods: A retrospective study was performed using clinical data from all inpatients from five hospitals with IPD from 2016 to 2018 and the corresponding data on serotype and antimicrobial-non-susceptibility of pneumococcus. Vaccine-serotype-coverage was estimated. Patients were classified according to presence of comorbidities: healthy, without comorbidities; at-risk, included immunocompetent persons with specific medical conditions; high-risk, with immunocompromising conditions and others Results: 406 IPD cases were evaluated. Among 324 cases with information on medical conditions, children < 5 years were mostly healthy (55.9%), while presence of comorbidity prevailed in adults ≥ 18 years old (> 82.0%). Presence of ≥1 risk condition was reported in ≥ 34.8% of adults. High-risk conditions were more frequent than at-risk in all age groups. Among high-risk comorbidity (n = 211), cancer (28%), HIV/AIDS (25.7%) and hematological diseases (24.5%) were the most frequent. Among at-risk conditions (n = 89), asthma (16.5%) and diabetes (8.1%) were the most frequent. Among 404 isolates, 42.9% belonged to five serotypes: 19A (14.1%), 3 (8.7%), 6C (7.7%), 4 and 8 (6.2% each); 19A and 6C expressed antimicrobial-non-susceptibility. The vaccine-serotype-coverage was: PCV10, 19.1%, PCV13, 43.8%; PCV15, 47.8%; PCV20, 62.9%; PCV21, 65.8%, and PPV23, 67.3%. Information on hospital outcome was available for 283 patients, of which 28.6% died. Mortality was 54.2% for those with meningitis. Conclusion: Vaccine with expanded valence of serotypes is necessary to offer broad prevention to IPD. The present data contribute to pneumococcal vaccination public health policies for vulnerable patients, mainly those with comorbidity and the elderly.

Chronic medical conditions associated with invasive pneumococcal diseases in inpatients in teaching hospitals in São Paulo city: Estimating antimicrobial susceptibility and serotype-coverage of pneumococcal vaccines

Background: Chronic conditions increase the risk of invasive pneumococcal diseases (IPD). Pneumococcal vaccination remarkably reduced IPD morbimortality in vulnerable populations. In Brazil, pneumococcal vaccines are included in the National Immunization Program (PNI): PCV10 for < 2 years-old, and PPV23 for high risk-patients aged ≥ 2 years and institutionalized ≥ 60 years. PCV13 is available in private clinics and recommended in the PNI for individuals with certain underlying conditions. Methods: A retrospective study was performed using clinical data from all inpatients from five hospitals with IPD from 2016 to 2018 and the corresponding data on serotype and antimicrobial-non-susceptibility of pneumococcus. Vaccine-serotype-coverage was estimated. Patients were classified according to presence of comorbidities: healthy, without comorbidities; at-risk, included immunocompetent persons with specific medical conditions; high-risk, with immunocompromising conditions and others RESULTS: 406 IPD cases were evaluated. Among 324 cases with information on medical conditions, children < 5 years were mostly healthy (55.9%), while presence of comorbidity prevailed in adults ≥ 18 years old (> 82.0%). Presence of ≥1 risk condition was reported in ≥ 34.8% of adults. High-risk conditions were more frequent than at-risk in all age groups. Among high-risk comorbidity (n = 211), cancer (28%), HIV/AIDS (25.7%) and hematological diseases (24.5%) were the most frequent. Among at-risk conditions (n = 89), asthma (16.5%) and diabetes (8.1%) were the most frequent. Among 404 isolates, 42.9% belonged to five serotypes: 19A (14.1%), 3 (8.7%), 6C (7.7%), 4 and 8 (6.2% each); 19A and 6C expressed antimicrobial-non-susceptibility. The vaccine-serotype-coverage was: PCV10, 19.1%, PCV13, 43.8%; PCV15, 47.8%; PCV20, 62.9%; PCV21, 65.8%, and PPV23, 67.3%. Information on hospital outcome was available for 283 patients, of which 28.6% died. Mortality was 54.2% for those with meningitis. Conclusion: Vaccine with expanded valence of serotypes is necessary to offer broad prevention to IPD. The present data contribute to pneumococcal vaccination public health policies for vulnerable patients, mainly those with comorbidity and the elderly. Keywords: Antimicrobial resistance; Chronic diseases; Comorbidity; Invasive pneumococcal diseases; Pneumococcal conjugate vaccine; Pneumococcal serotypes; Pneumococcal vaccine.

Critérios sorológicos de proteção contra doença invasiva em crianças após vacina pneumocócica conjugada / Protective serological criteria against invasive disease after pneumococcal conjugate vaccine in children

Infecções causadas pelo S. pneumoniae são associadas à elevada morbidade e mortalidade, particularmente em lactentes e crianças pequenas. As vacinas polissacarídicas conjugadas a um complexo protéico demonstraram ser extremamente imunogênicas em lactentes, induzindo imunidade dependente de células T. Uma vacina pneumocócica conjugada heptavalente, usando como carreador protéico para os sete sorotipos o mutante diftérico CRM197, foi licenciada nos Estados Unidos no ano 2000, demonstrando ser segura, induzindo elevados títulos de anticorpos séricos, memória imunológica e ainda reduzindo, entre os vacinados, o estado de portador em nasofaringe dos sorotipos incluídos em sua composição. Neste momento, encontra-se em estágio avançado de desenvolvimento várias vacinas pneumocócicas conjugadas. Com o objetivo precípuo de estabelecer um parâmetro para ser utilizado no licenciamento de novas vacinas pneumocócicas conjugadas candidatas, em função de limitações de ordem ética e prática para realização de estudos de eficácia clínica, e baseando-se nos dados de três grandes estudos controlados, duplo-cegos, de eficácia clínica (dois nos EUA e um na África do Sul) a OMS recomendou, recentemente, a adoção de títulos de anticorpos anticapsulares polissacarídicos da classe IgG, medidos pelo método de ELISA, ³ 0,35 µg/mL, avaliados um mês após o término da imunização primária como sendo a concentração mínima de anticorpos associados à eficácia clínica protetora contra doença pneumocócica invasiva.