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.

Behavioral factors associated with multiple-type HPV genital infections: data from a cross-sectional study in young women in Brazil.

OBJECTIVES: To investigate the pattern of multiple human papillomavirus (HPV) infections and associated factors in young women who access the Brazilian public health care system to better understand the characteristics of multiple HPV infections, a critical issue in this era of multivalent vaccines. METHODS: This was a cross-sectional, multicenter study with sexually active unvaccinated women (16-25 years old) from 119 primary Brazilian healthcare centers between September 2016 and November 2017. Cervical samples were collected by trained health professionals, and HPV detection was performed in a central laboratory by Linear Array. RESULTS: Of the 5268 women, 33.00% (95% CI 31.07-34.92) had multiple infections. At least one type of high-risk HPV was present in 85.50% of all multiple infections. All HPV types were detected more frequently in association with other types than alone. Young individuals who were single or in a casual relationship and those who had more than one sexual partner in the past year were more likely to have multiple infections. CONCLUSIONS: In this work, a high rate of multiple HPV infections among unvaccinated young adults tended to increase due to certain risk factors. Such data can provide insight for decision makers in the development of public policies regarding HPV prevention.

Understanding the characteristics of multiple infections is critical in the era of HPV multivalent vaccines for the prevention of cervical carcinomas. Therefore, in this cross-sectional study, we aimed to investigate the pattern of multiple HPV infections and associated factors in 5,268 sexually active unvaccinated women (16­25 years old) who access the Brazilian public health care system. Cervical samples were collected by trained health professionals, and HPV detection was performed in a central laboratory by Linear Array. A total of 33.00% (95% CI 31.07­34.92) had multiple infections (60.43% of the HPV-positive sample). The number of HPV types in a multiple infection ranged from 2 to 14 different types. The viral types more frequently identified were HPV 16 and 52. All HPV types were detected more frequently in association with other types than alone. The incidence of multiple infections was 1.29 times higher in single than in married or cohabitating participants. Women who had two or more partners in the last year also had higher rates of multiple infections than those who had fewer than two sexual partners. In conclusion, a high prevalence of multiple infections prior to the national HPV immunization program was observed, especially with the increase in less safe behavior factors.

17DD Yellow Fever Revaccination and Heightened Long-Term Immunity in Populations of Disease-Endemic Areas, Brazil.

We evaluated the duration of neutralizing antibodies and the status of 17DD vaccine-specific T- and B-cell memory following primary and revaccination regimens for yellow fever (YF) in Brazil. We observed progressive decline of plaque-reduction neutralization test (PRNT) seropositivity and of the levels of effector memory CD4+ and CD8+ T cells, as well as interferon-γ+CD8+ T cells, 10 years after primary vaccination. Revaccination restored PRNT seropositivity as well as the levels of effector memory CD4+, CD8+, and interferon-γ+CD8+ T cells. Moreover, secondary or multiple vaccinations guarantee long-term persistence of PRNT positivity and cell-mediated memory 10 years after booster vaccination. These findings support the relevance of booster doses to heighten the 17DD-YF-specific immune response to guarantee the long-term persistence of memory components. Secondary or multiple vaccinations improved the correlates of protection triggered by 17DD-YF primary vaccination, indicating that booster regimens are needed to achieve efficient immunity in areas with high risk for virus transmission.

[Analysis of the Vaccine Adverse Event Reporting System in Brazil, 2014 to 2016Análisis del Sistema de Información de Vigilancia de Eventos Adversos Posvacunación en Brasil, 2014 a 2016]. / Análise do Sistema de Informação da Vigilância de Eventos Adversos Pós-Vacinação no Brasil, 2014 a 2016.

OBJECTIVE: To describe the characteristics of vaccine adverse events (VAE) reports in the online VAE Reporting System (VAE-RS) after 2 years of operation. METHOD: A descriptive analysis of VAE reports entered into the VAE-RS between July 2014 and June 2016 was performed. RESULTS: During the study period, 24 732 VAE were reported. Of 5 570 Brazilian municipalities, 2 571 (46.2%) reported at least one VAE; however, only 1 622 (6.6%) reports had been completed/closed at the end of the study period. Of these, 89.9% referred to mild VAE. Among the completed reports, 19.7% did not provide information on "type of medical care provided," and 98.7% had no information regarding laboratory tests. Systemic neurological symptoms were the most frequent serious VAE among closed reports (59.5% of serious signs/symptoms). Concerning age, the highest VAE reporting coefficients were recorded for children aged ≤ 4 years. CONCLUSION: The VAE-RS is useful to monitor immunization safety. However, municipal services must increase adherence to the system and perform the required investigation and reporting of VAE, with timely and adequate completion of the VAE-RS form. Knowledge regarding VAE can be used in the daily routine of surveillance services, improving the safety of immunobiological agents.

OBJETIVO: Describir las características de las notificaciones de eventos adversos posvacunación (EAPV) en el Sistema de Información de Vigilancia de EAPV (SI-EAPV, un sistema en línea, durante los primeros 2 años de ejecución del sistema. MÉTODO: Se realizó un estudio descriptivo de los registros de EAPV notificados en el SI-EAPV entre julio de 2014 y junio de 2016. RESULTADOS: Durante el período del estudio, se registraron 24 732 notificaciones. De 5 570 municipios brasileños, 2 571 (46,2%) notificaron algún EAPV. Sin embargo, solamente 1 622 (6,6%) notificaciones estaban cerradas al momento del estudio; de ellas, el 89,9% no presentó gravedad. Respecto a las notificaciones cerradas, en el 19,7% no fue anotada la variable "atención médica" y el 98,7% no presentó registro de exámenes de laboratorio. Entre los eventos adversos graves cerrados, las manifestaciones clínicas sistémicas neurológicas fueron las más frecuentes, representado el 59,5% de los signos y síntomas. En cuanto a la edad, los mayores coeficientes de notificación se registraron entre los menores de 4 años. CONCLUSIÓN: El SI-EAPV es útil para el monitoreo de la seguridad de las vacunas. Sin embargo, los municipios necesitan ampliar la adhesión al sistema, así como realizar las investigaciones y notificaciones de los EAPV, llenando la ficha de notificación de forma adecuada y oportuna. El conocimiento sobre EAPV puede ser aplicado en la práctica de los servicios de vigilancia en salud, mejorando la seguridad en la utilización de los productos inmunobiológicos.

Introduction of sequential inactivated polio vaccine-oral polio vaccine schedule for routine infant immunization in Brazil's National Immunization Program.

In August 2012, the Brazilian Ministry of Health introduced inactivated polio vaccine (IPV) as part of sequential polio vaccination schedule for all infants beginning their primary vaccination series. The revised childhood immunization schedule included 2 doses of IPV at 2 and 4 months of age followed by 2 doses of oral polio vaccine (OPV) at 6 and 15 months of age. One annual national polio immunization day was maintained to provide OPV to all children aged 6 to 59 months. The decision to introduce IPV was based on preventing rare cases of vaccine-associated paralytic polio, financially sustaining IPV introduction, ensuring equitable access to IPV, and preparing for future OPV cessation following global eradication. Introducing IPV during a national multivaccination campaign led to rapid uptake, despite challenges with local vaccine supply due to high wastage rates. Continuous monitoring is required to achieve high coverage with the sequential polio vaccine schedule.

Complete vaccination coverage of children born in 2017-2018, living in urban areas of state capitals and in 12 inland cities in Brazil: a population-based survey from a retrospective cohort study.

OBJECTIVE: To estimate vaccination coverage in children born between 2017-2018, living in urban areas of state capitals, the Federal District and 12 inland municipalities in Brazil, and to identify associated factors. METHODS: This was a household survey conducted between 2020-2022, among children up to 24 months old. Vaccination coverage was estimated according to family, maternal and child characteristics. RESULTS: Among the 37,801 children in the sample, complete coverage (doses administered) was 60.1% (95%CI 58.6;61.6) and 6.1% (95%CI 5.4;7.0) had not received any vaccines. Coverage was lower among children of mothers with lower level of education (OR = 0.70; 95%CI 0.54;0.90) and in those who experienced delays in receiving any vaccine by 6 months old (OR = 0.28; 95%CI 0.24;0.32). CONCLUSION: Vaccination coverage is below the expected levels. Effective communication strategies are needed to reinforce the importance of routine vaccination, prevent delays and abandonment of the vaccination schedule, in order to recover the high coverage levels achieved in past decades.

MAIN RESULTS: Vaccination coverage with the complete schedule, excluding yellow fever, was 60% and lower among mothers with low education level and in children with delayed vaccination. With the exception of the intradermal BCG vaccine, the other vaccines did not reach the recommended levels. IMPLICATIONS FOR SERVICES: The vaccination process in primary healthcare centers can be improved by enabling the simultaneous administration of doses scheduled in a single session and implementing active search for absentees in order to reduce delayed vaccination and enhance access. PERSPECTIVES: The discussion of the results across the three levels of management can support proposals to improve the functioning of health services, especially the operational process in vaccination rooms, aimed at improving vaccination coverage.

Hepatitis A vaccination coverage survey in 24-month-old children living in Brazilian capitals, 2020.

OBJECTIVE: To estimate hepatitis A vaccination coverage in 24-month-old children and identify factors associated with non-vaccination. METHODS: This was a survey involving a sample stratified by socioeconomic strata in capital cities (2020-2022), with coverage estimates and 95% confidence intervals (95%CI), the factor analysis was performed using the prevalence ratio (PR) by means of Poisson regression. RESULTS: Among 31,001 children, hepatitis A coverage was 88.1% (95%CI 86.8;89.2). Regarding socioeconomic strata (A/B), the variable immigrant parents/guardians was associated with non-vaccination (PR = 1.91; 95%CI 1.09;3.37); in strata C/D, children of Asian race/skin color (PR = 4.69; 95%CI 2.30;9.57), fourth-born child or later (PR = 1.68; 95%CI 1.06;2 .66), not attending daycare/nursery (PR = 1.67; 95%CI 1.24;2.24) and mother with paid work (PR = 1.42; 95%CI 1.16;1.74) were associated with non-vaccination. CONCLUSION: Hepatitis A coverage was below the target (95%), suggesting that specificities of social strata should be taken into consideration. MAIN RESULTS: Hepatitis A vaccination coverage was 88%. Non-vaccination was greater in children with immigrant guardians (strata A/B); of Asian race/skin color, fourth-born child or later, those not attending daycare/nursery and mother with paid work (C/D strata). IMPLICATIONS FOR SERVICES: The results of this study contributed to the Ministry of Health and Health Departments in monitoring vaccination coverage and identifying factors that may negatively impact hepatitis A vaccination coverage. PERSPECTIVES: Further research is needed on the impact of migration on hepatitis A vaccination and vaccination in general. Health managers should be attentive to the different factors affecting vaccination among social strata.

Vaccination coverage, hesitancy and associated factors: a household survey of a cohort of children born in 2017 and 2018 in urban areas of state capital cities in the Brazilian Northeast.

OBJECTIVE: To estimate vaccination coverage and analyze sociodemographic factors associated with non-vaccination in children born in 2017 and 2018 in the state capitals of Northeast Brazil. METHODS: A household survey using cluster sampling was conducted from 2020-2022 to estimate vaccination coverage and hesitancy. Factors associated with non-vaccination were analyzed using logistic regression to calculate Odds Ratios (OR) and their Confidence Intervals (95%CI). RESULTS: Natal was the capital with the lowest vaccination coverage, below 75.0% for most immunizers. Teresina had rates equal to or greater than 90.0% for all vaccines. Among those interviewed, 99.1% (95%CI 98.9;99.3) believe that vaccines are important for health; 95.4% (95%CI 95.0;95.8) trust immunobiologicals and 79.6% (95%CI% 78.8;80.3) are not afraid of reactions. Belonging to the highest socioeconomic stratum (adjusted OR: 1.34 - 95%CI 1.20;1.50) was as a factor associated with non-vaccination. CONCLUSION: Low coverage highlights the need for a better understanding of regional specificities and social inequalities.

MAIN RESULTS: Three northeastern capitals achieved targets for just two or three vaccines. The majority of interviewees expressed favorable opinions regarding the National Immunization Program. However, a third of those interviewed reported that they had sought vaccination but had been unable to vaccinate their children. IMPLICATIONS FOR SERVICES: Rethinking immunization strategies in the Brazilian National Health System, to adapt them to regional contexts. Operational obstacles related to the supply of vaccines require special attention, in addition to integrated health communication and education actions. PERSPECTIVES: Understanding the regional specificities presented will support the National Immunization Program in implementing strategies contextualized to territories, via microplanning of vaccination actions, to recover vaccination coverage.

Vaccine coverage by social strata in state capitals in the Brazilian Midwest region: a household survey of children born in 2017 and 2018.

OBJECTIVE: To analyze full vaccination coverage in live births in 2017 and 2018 in the capitals of the Midwest region of Brazil, according to social strata. METHODS: Population-based household survey with cluster sampling. Full coverage in children at 12 and 24 months of age and sociodemographic factors were analyzed. RESULTS: 5,715 children were analyzed. Full coverage at 12 months of age was 67.9% (95%CI 65.4;70.4), while at 24 months it was 48.2% (95%CI 45.3;51.1). Pneumococcal vaccine had the highest vaccination coverage (91.3%), while the second dose of rotavirus vaccine had the lowest (74.2%). In Campo Grande, no vaccine reached coverage above 90%, with BCG (82.9%) and hepatitis B (82.1%) standing out. Campo Grande and Brasília had the worst vaccination coverage in the high social stratum (24 months of age). CONCLUSION: Vaccination coverage in the Midwest was below 80%, falling short of the recommended target and associated with socioeconomic factors.

MAIN RESULTS: Vaccination coverage at 24 months old among the Midwest state capitals ranged between 39.9% in Campo Grande and 54.5% in Brasília. All vaccination coverage was below the target recommended by the National Immunization Program. IMPLICATIONS FOR SERVICES: The results found point to the urgent need for planning actions aimed at improving vaccination coverage with targeted approaches, considering social strata and vaccines with lower vaccination coverage. PERSPECTIVES: Future research that investigates vaccination coverage in the Midwest region may assist in understanding the low vaccination coverage found for most recommended vaccines, especially in the first 24 months of life.

Immune response induced by standard and fractional doses of 17DD yellow fever vaccine.

The re-emergence of yellow fever (YF) urged new mass vaccination campaigns and, in 2017, the World Health Organization approved the use of the fractional dose (FD) of the YF vaccine due to stock shortage. In an observational cross-sectional investigation, we have assessed viremia, antibodies, soluble mediators and effector and memory T and B-cells induced by primary vaccination of volunteers with FD and standard dose (SD). Similar viremia and levels of antibodies and soluble markers were induced early after immunization. However, a faster decrease in the latter was observed after SD. The FD led to a sustained expansion of helper T-cells and an increased expression of activation markers on T-cells early after vaccination. Although with different kinetics, expansion of plasma cells was induced upon SD and FD immunization. Integrative analysis reveals that FD induces a more complex network involving follicular helper T cells and B-cells than SD. Our findings substantiate that FD can replace SD inducing robust correlates of protective immune response against YF.

Comprehensive landscape of neutralizing antibody and cell-mediated response elicited by the 1/5 fractional dose of 17DD-YF primary vaccination in adults.

The present study aimed at evaluating the YF-specific neutralizing antibody profile besides a multiparametric analysis of phenotypic/functional features of cell-mediated response elicited by the 1/5 fractional dose of 17DD-YF vaccine, administered as a single subcutaneous injection. The immunological parameters of each volunteer was monitored at two time points, referred as: before (Day 0) [Non-Vaccinated, NV(D0)] and after vaccination (Day 30-45) [Primary Vaccinees, PV(D30-45)]. Data demonstrated high levels of neutralizing antibodies for PV(D30-45) leading to a seropositivity rate of 93%. A broad increase of systemic soluble mediators with a mixed profile was also observed for PV(D30-45), with IFN-γ and TNF-α presenting the highest baseline fold changes. Integrative network mapping of soluble mediators showed increased correlation numbers in PV(D30-45) as compared to NV(D0) (532vs398). Moreover, PV(D30-45) exhibited increased levels of Terminal Effector (CD45RA+CCR7-) CD4+ and CD8+ T-cells and Non-Classical memory B-cells (IgD+CD27+). Dimensionality reduction of Mass Cytometry data further support these findings. A polyfunctional cytokine profile (TNF-α/IFN-γ/IL-10/IL-17/IL-2) of T and B-cells was observed upon in vitro antigen recall. Mapping and kinetics timeline of soluble mediator signatures for PV(D30-45) further confirmed the polyfunctional profile upon long-term in vitro culture, mediated by increased levels of IFN-γ and TNF-α along with decreased production of IL-10. These findings suggest novel insights of correlates of protection elicited by the 1/5 fractional dose of 17DD-YF vaccine.

Racial inequalities in child vaccination and barriers to vaccination in Brazil among live births in 2017 and 2018: an analysis of a retrospective cohort of the first two years of life.

OBJECTIVE: To describe timely vaccination completion and obstacles in the first 24 months of life in Brazil, examining associations with maternal race/skin color. METHODS: Study participants were 37,801 children born in 2017 and 2018 included in the National Immunization Coverage Survey. We calculated prevalence and 95% confidence intervals for timely vaccine completeness and obstacles at 5, 12 and 24 months of life, according to maternal race/skin color. Associations were analyzed using logistic regression. RESULTS: 7.2% (95%CI 6.3;8.2) of mothers faced difficulties in taking their children to be vaccinated, and 23.4% (95%CI 21.7;25.1) were not vaccinated when taken. These proportions were 75% (95%CI 1.25;2.45) and 97% (95%CI 1.57;2.48) higher, respectively, among Black mothers. At least one vaccination was delayed among 49.9% (95%CI 47.8;51.9) and 61.1% (95%CI 59.2;63.0) of children by 5 and 12 months, respectively. These rates were higher among Black/mixed race mothers. CONCLUSION: There are racial inequalities in both the obstacles faced and in vaccination rates in Brazil. MAIN RESULTS: Marked racial inequalities were found in the obstacles to vaccination of children under 24 months in Brazil and to timely vaccination at 5 months and in the first year of life. IMPLICATIONS FOR SERVICES: Racial inequalities in the occurrence of vaccination shortcomings in health services, in the objective restrictions faced by families in taking their children to vaccination centers and in incomplete vaccination in a timely manner need to be addressed by the Brazilian National Health System. PERSPECTIVES: Equal public policies to address barriers to vaccination and qualification of health services need to be implemented. Studies need to deepen understanding of the structural determinants that lead to racial disparities.

Description of vaccination coverage and hesitancy obtained by epidemiological survey of children born in 2017-2018, in Belo Horizonte and Sete Lagoas, Minas Gerais, Brazil.

OBJECTIVE: To describe vaccination coverage and hesitation for the basic children's schedule in Belo Horizonte and Sete Lagoas, Minas Gerais state, Brazil. METHODS: Population-based epidemiological surveys performed from 2020 to 2022, which estimated vaccine coverage by type of immunobiological product and full schedule (valid and ministered doses), according to socioeconomic strata; and reasons for vaccination hesitancy. RESULTS: Overall coverage with valid doses and vaccination hesitancy for at least one vaccine were, respectively, 50.2% (95%CI 44.1;56.2) and 1.6% (95%CI 0.9;2.7), in Belo Horizonte (n = 1,866), and 64.9% (95%CI 56.9;72.1) and 1.0% (95%CI 0.3;2.8), in Sete Lagoas (n = 451), with differences between socioeconomic strata. Fear of severe reactions was the main reason for vaccination hesitancy. CONCLUSION: Coverage was identified as being below recommended levels for most vaccines. Disinformation should be combated in order to avoid vaccination hesitancy. There is a pressing need to recover coverages, considering public health service access and socioeconomic disparities. MAIN RESULTS: Vaccination coverage of children up to 4 years old was 50.2% in Belo Horizonte, and 64.9% in Sete Lagoas. Fear of severe reactions and believing that vaccination against eradicated diseases is unnecessary were the main reasons for vaccination hesitancy. IMPLICATIONS FOR SERVICES: Recovery of high vaccination coverage among children, considering public health service access conditions and socioeconomic inequities. Acting on reasons for hesitancy that can assist in targeting actions. PERSPECTIVES: The multifactorial context of vaccination hesitancy demands the development of health education strategies to raise awareness about child immunization.

Vaccination coverage and delay in vaccination of infants born in 2017 and 2018 in municipalities in the Southern region of Brazil: National Vaccination Coverage Survey 2020.

OBJECTIVE: To evaluate vaccination coverage and delay in vaccine dose administration in infants in six municipalities in the Southern region of Brazil. METHODOLOGY: National Vaccination Coverage Survey 2020, with infants born alive in 2017 and 2018, carried out from September 2020 to March 2022. Coverage of doses administered, doses administered on time and delay in dose administration were evaluated. RESULTS: For 4681 infants analyzed, coverage for vaccines recommended up to 24 months was 68.0% (95%CI 63.9;71.8%) for doses administered and 3.9% (95%CI 2.7%;5.7%) for doses administered on time. Delay time for the majority of late vaccinations was ≤ 3 months. For some boosters, 25% of vaccine administration was delayed by ≥ 6 months. CONCLUSION: In addition to tracking vaccine defaulters, strategies are needed to encourage compliance with the vaccination schedule at the recommended ages. MAIN RESULTS: Vaccination coverage for the set of vaccines recommended up to 24 months was 68.0% and 3.9% for on-time doses. Delay time for some doses exceeded six months in up to 25% of infants with delayed vaccination. IMPLICATIONS FOR SERVICES: Monitoring vaccine administration at the recommended ages is necessary, with the adoption of strategies that reinforce routine vaccination to prevent vaccination delays and abandonment. PERSPECTIVES: Primary care in surveillance and care for infants needs to reinforce actions to ensure timely vaccination. Studies to deepen knowledge of vaccination delay, determinants and strategies for their reduction are necessary.

Reliability of information recorded on the National Immunization Program Information System.

OBJECTIVE: To analyze the reliability of records held on the National Immunization Program Information System (SI-PNI) in a subsample of children included in the national vaccination coverage survey in Brazilian state capitals and Federal District in 2020. METHODS: This was a study of agreement between data recorded on vaccination cards (doses and dates) and on the SI-PNI for 4050 children with full coverage at 24 months. RESULTS: Data on 3587 children were held on the SI-PNI, with losses of 11% (95%CI: 10;12). Total agreement between doses and dates in the two sources was 86% (95%CI: 86;87), however taking each dose and vaccine individually, variation was greater, with 32% of data in only one source. CONCLUSION: Part of the information was not recorded, but the discrepancy can be considered small. Nonetheless, underrecording of doses and children can compromise vaccination coverage estimates, altering the numerator and denominator data. MAIN RESULTS: Subsample of 4,050 children, among those completing the full schedule at 24 months studied in the national survey, 11% had not been recorded on the SI-PNI, 32% had unrecorded doses (doses or dates) and there was 8% disagreement between vaccination cards and SI-PNI records. IMPLICATIONS FOR SERVICES: Recognizing the difficulties faced by the SI-PNI and the discrepancies between sources is essential for adopting initiatives to improve data quality, so as to avoid inaccurate estimates of childhood vaccination coverage. PERSPECTIVES: This study is expected to contribute to improving the quality of records and the usability of data for monitoring vaccination coverage of the immunization program from the local to the national level.

Vaccination coverage survey by social stratum in children up to 24 months of age in Londrina, Paraná, Brazil, between 2021 and 2022.

OBJECTIVE: To analyze vaccination coverage according to social strata in children up to 24 months old, living in the municipality of Londrina (PR), Brazil. METHODS: This was a population-based survey conducted between 2021 and 2022, in which vaccination coverage and sociodemographic aspects of mothers and families were evaluated using Pearson's chi-square test. RESULTS: In a sample of 456 children, complete vaccination coverage varied according to social strata, being 36.0% (95%CI 26.8;57.8); in stratum A; 59.5% (95%CI 26.1;86); in stratum B; 66.2% (95%CI 51.7;78.1); in stratum C; and 70.0% (95%CI 56.1;81.0) in stratum D. CONCLUSION: The analysis of vaccination coverage indicated that social stratum A is at highest risk for vaccine-preventable diseases. MAIN RESULTS: The results of the study showed low full vaccination coverage in children up to 24 months of age in Londrina, being higher in the less financially advantaged social stratum, compared to the most advantaged. IMPLICATIONS FOR SERVICES: The results found can support the qualification of the immunization program and enable, based on planning and ongoing health education, the definition of unique strategies to improve vaccination coverage. PERSPECTIVES: Future perspectives point to the importance of carrying out investigations into the challenges inherent to vaccination, as well as qualitative and quantitative research addressing health professionals to better understand the data.

Vaccination coverage, barriers and vaccine hesitancy in children up to 24 months old: a population survey in a state capital in the Western Amazon.

OBJECTIVE: To estimate vaccination coverage, identify barriers and hesitancy to vaccinating children up to 24 months, born between 2017-2018, living in the urban area of Rio Branco, Acre, Brazil. METHODS: Population survey carried out from 2020 to 2021, which assessed sociodemographic characteristics and vaccination status among children. RESULTS: Among 451 included children, vaccination coverage was below 80%. Meningococcal C vaccine had the lowest coverage for administered doses (76.3%; 95%CI 70.5;81.3) and doses on time (27.4%; 95%CI 23.1;32.1). The statements "vaccines cause serious adverse reactions" (26.4%; 95%CI 18.1;36.8) and "you don't need vaccination for diseases that no longer exist" (22%; 95%CI 15.7;29.8) were the most frequent regarding vaccination hesitancy. Lack of vaccines was the main barrier to care (86.6%; 95%CI 71.8;94.3). CONCLUSION: Vaccination coverage in children born in 2017-2018 was below the target recommended for the full schedule of administered doses, both valid and timely administered.

MAIN RESULTS: Coverage levels below 80%. Main barriers: access difficulties and lack of vaccines. Believing that events supposedly attributable to vaccination are serious was the most frequent statement justifying vaccination hesitancy. IMPLICATIONS FOR SERVICES: It is necessary to avoid loss of vaccination opportunities, guaranteeing vaccines and qualified professionals in health centers, in addition to providing guidance to the community on the vaccination schedule and its intervals. PERSPECTIVES: Prospective and qualitative studies help to assess associated factors and understand barriers and vaccination hesitancy; evaluating the cost-effectiveness of programs aimed at the role of health professionals is essential.

Use of private vaccination services by infants in Brazilian municipalities: National Vaccine Coverage Survey 2020.

OBJECTIVE: To characterize the use of private services in infant vaccination and assess vaccination coverage according to the service used. METHODS: : This was a national vaccination survey conducted in 2020 that estimated the use of private vaccination services and vaccination coverage among infants residing in state capitals and 12 inland municipalities. RESULTS: : Of the 37,801 participants, 25.1% (95%CI 23.2;27.2) used private services at least once, with higher proportions in capitals, larger cities and in the South and Southeast regions. Socioeconomic and demographic differences were identified among families, based on the service used. The coverage for the set of vaccines administered up to 24 months was 60.3% (95%CI 58.6;62.0) in the public service and 59.5% (95%CI 55.9;63.0) in private services, and up-to-date vaccines, 10.3% (95%CI 9.1;11.6) and 9.4% (95%CI 7.4;11.8), respectively. CONCLUSION: The use of private services was frequent, with low coverage for the set of vaccines, regardless of the type of service used, especially for up-to-date vaccines.

MAIN RESULTS: The use of private vaccination services was observed in 25% of the municipalities studied, as well as low complete vaccination coverage in children up to 24 months old in both private and public services, especially for up-to-date vaccines. IMPLICATIONS FOR SERVICES: The increasing role of private vaccination services highlights the importance of coordination between immunization program managers at all levels and private vaccination services. PERSPECTIVES: Monitoring the vaccination status and conducting studies to understand the factors associated with incomplete and delayed vaccination are necessary. Such research can contribute to the adoption of new strategies that also include private vaccination services.

Effect of 10-valent pneumococcal vaccine on pneumonia among children, Brazil.

Pneumonia is most problematic for children in developing countries. In 2010, Brazil introduced a 10-valent pneumococcal conjugate vaccine (PCV10) to its National Immunization Program. To assess the vaccine's effectiveness for preventing pneumonia, we analyzed rates of hospitalization among children 2-24 months of age who had pneumonia from all causes from January 2005 through August 2011. We used data from the National Hospitalization Information System to conduct an interrupted time-series analysis for 5 cities in Brazil that had good data quality and high PCV10 vaccination coverage. Of the 197,975 hospitalizations analyzed, 30% were for pneumonia. Significant declines in hospitalizations for pneumonia were noted in Belo Horizonte (28.7%), Curitiba (23.3%), and Recife (27.4%) but not in São Paulo and Porto Alegre. However, in the latter 2 cities, vaccination coverage was less than that in the former 3. Overall, 1 year after introduction of PCV10, hospitalizations of children for pneumonia were reduced.

Vaccination coverage in children in the period before and during the COVID-19 pandemic in Brazil: a time series analysis and literature review.

OBJECTIVE: To evaluate the behavior of VCR and VCH, per municipality and per vaccines offered at the NVC, to identify priority areas for intervention. METHODS: Descriptive study of a time series, using secondary data and accompanied by a narrative review of the literature evaluating VCR and VCH. Vaccines offered to children under one year and to those aged one year in the pre-pandemic period of COVID-19 (2015 to 2019) were selected and compared to those offered during the pandemic period (2020 and 2021). RESULTS AND DISCUSSIONS: The decrease in VCR and VCH is a process that precedes the COVID-19 pandemic but was intensified during this period. In 2021, the VCR was around 70% for most vaccines. This phenomenon encompasses the entire country; however, it is more intense in the states/municipalities located in the north and northeast regions, suggesting greater difficulty in accessing health services. CONCLUSIONS: Low and heterogeneous VCR requires the adoption of practices that were previously implemented, establishing partnerships with governmental and non-governmental institutions, with adequate communication, active search for non-compliance and non-adherence to the regular vaccination program, adopting intra- and extramural vaccination strategies, to reverse the current situation and reduce the risk of recurrence of diseases that have been already controlled and eliminated.