The effectiveness of nirsevimab in reducing the burden of disease due to respiratory syncytial virus (RSV) infection over time in the Madrid region (Spain): a prospective population-based cohort study.

Introduction: Respiratory syncytial virus (RSV) infection is one of the main causes of morbidity and mortality from lower respiratory tract infections in children under 5 years of age worldwide. Given that, the objective of this study was estimate the effectiveness of nirsevimab (a single-dose, long-acting, human recombinant monoclonal antibody against RSV) over time for the prevention of respiratory episodes treated at different levels of care. Methods: A prospective and dynamic population-based cohort study was performed including infants born between April 1 and December 31, 2023, in the Madrid region who resided there during the follow-up period from October 1, 2023, to February 29, 2024. Infants were considered immunized from the day after receiving one dose (50 or 100 mg) of nirsevimab or nonimmunized individuals if they did not receive any dose. Results: There were 4,100 episodes of primary care, 1,954 hospital emergencies, and 509 admissions, 82 of which required intensive care in the 33,859 participants analyzed. The adjusted effectiveness of nirsevimab in preventing hospitalization due to RSV infection was 93.6% (95% CI: 89.7 to 96.1) at 30 days and 87.6% (95% CI: 67.7 to 95.3) at 150 days. The number needed to treat to prevent one hospitalization were 314.19 (95% CI: 306.22 to 327.99) at 30 days and 24.30 (95% CI: 22.31 to 31.61) at 150 days. The adjusted effectiveness of nirsevimab in avoiding admission to an intensive care unit was 94.4% (95% CI: 87.3 to 97.5) at 30 days and 92.1% (95% CI: 64.0 to 98.3) at 90 days. The adjusted effectiveness of nirsevimab for avoiding primary care consultations and hospital emergency visits was lower. Discussion: Immunization with nirsevimab is an effective measure for reducing the burden of care related to RSV at all levels of care albeit it decreases throughout follow-up. At 150 days it remained high for preventing hospital admissions. Other articles already published have also demonstrated high effectiveness although with preliminary results, short follow-up periods and wide confidence intervals. None have detected a decrease in effectiveness over time. These results can be quite useful in individual infant prevention and in the design of immunization campaigns.

Acceptance and socioeconomic inequalities in meningococcal B vaccination in the community of Madrid prior to its inclusion in the immunization schedule.

INTRODUCTION: The main preventive measure against invasive meningococcal disease is vaccination. The aim of our study was to evaluate the acceptability of the meningococcal B (MenB) vaccine and socioeconomic inequalities in the access to the vaccine in the Community of Madrid in the period prior to its introduction in the immunization schedule. MATERIALS AND METHODS: We conducted an observational and ecological descriptive study in the cohort of children born between 2016 and 2019 using population-based electronic records. We calculated the vaccination coverage and analysed factors associated with vaccination status, determined the spatial distribution of vaccination coverage and the deprivation index (DI) and assessed the association between them by means of spatial regression. RESULTS: We observed an increasing trend in primary vaccination coverage, from 44% in the cohort born in 2016 to 68% in the 2019 cohort. We found a statistically significant association between vaccination status and the DI (OR of primary vaccination in areas with DI5 compared to areas with DP1, 0.38; 95% confidence interval, 0.39-0.50; P<.001). The spatial analysis showed an inverse correlation between the DI and vaccination coverage. CONCLUSIONS: The rise in the coverages of the MenB vaccine shows acceptance by the population. The association between socioeconomic level and vaccination coverage confirms the existence of health inequality and underlines the importance including this vaccine in the immunization schedule.

Vaccination against influenza: Coverage and adherence in children under 15 years with high-risk medical conditions in the Community of Madrid.

INTRODUCTION: Vaccination against influenza is indicated in children at risk of complications or severe disease. The objective of this study was to describe the percentage of children aged less than 15 years with risk conditions vaccinated against influenza in the Community of Madrid, and to analyze the factors associated with adherence to vaccination throughout 3 vaccination campaigns. MATERIALS AND METHODS: Population-based cross-sectional observational study of children aged 6 months to 14 years with conditions that indicated influenza vaccination at the beginning of the 2018-2019 campaign. Electronic population registers were used. We described the percentage of children vaccinated in 3 consecutive campaigns, and assessed the association of adherence to vaccination with demographic and socioeconomic variables and risk conditions using bivariate and multivariate analysis. RESULTS: The vaccination coverage was 15.6% in the 2018-2019 campaign. The adherence to vaccination was 65.9%. The variables associated with greater adherence were age greater than 2 years, especially in the 6-10 years group (aOR = 1.63; 95% CI, 1.43-1.85) and presenting more than one risk condition, especially 3 or more diseases (aOR = 1.80; 95% CI, 1.00-3.26). Diabetes mellitus was the disease associated most strongly with adherence (aOR = 2.15; 95% CI, 1.74-2.65). Adherence was lower in the immigrant population (aOR = 0.43; 95% CI, 0.36-0.51). We found no association between vaccination adherence and sex or socioeconomic status. CONCLUSIONS: Vaccination coverage and adherence were suboptimal. Adherence to vaccination against influenza is associated with demographic and clinical conditions. Strategies need to be established to increase vaccination in children, with greater involvement of professionals and education of parents.

Effect of Primary Care Center Characteristics, Healthcare Worker Vaccination Status and Patient Economic Setting on Patient Influenza Vaccination Coverage Rates.

BACKGROUND: Reaching the public health organizations targets of influenza vaccination in at-risk patient groups remains a challenge worldwide. Recognizing the relationship between the healthcare system characteristics and the economic environment of the population with vaccination uptake can be of great importance to improve. METHODS: Several characteristics were correlated in this retrospective ecological study with data from 6.8 million citizens, 15,812 healthcare workers across 258 primary care health centers, and average income by area of the care center in Spain. RESULTS: No correlation between HCW vaccination status and patient vaccination was found. A weak negative significant correlation between the size of the population the care center covers and their vaccination status did exist (6 mo.-59 yr., r = 0.19, p = 0.002; 60-64 yr., r = 0.23, p < 0.001; ≥65 yr., r = 0.23, p ≥ 0.001). The primary care centers with fewer HCWs had better uptake in the at-risk groups in the age groups of 60-64 yr. (r = 0.20, p = 0.002) and ≥65 (r = 0.023, p ≥ 0.001). A negative correlation was found regarding workload in the 6 mo.-59 yr. age group (r = 0.18, p = 0.004), which showed the at-risk groups that lived in the most economically deprived areas were more likely to be vaccinated. CONCLUSIONS: This study reveals that the confounding variables that determine influenza vaccination in a population and in HCWs are complex. Future influenza campaigns should address these especially considering the possibility of combining influenza and SARS-CoV-2 vaccines each year.

Increasing Influenza Vaccination in Primary Healthcare Workers Using Solidary Incentives: Analysis of Efficacy and Costs.

INTRODUCTION: Influenza vaccination campaigns have difficulty in reaching the 75% uptake in healthcare workers (HCWs) that public health organizations target. This study runs a campaign across 42 primary care centers (PCCs) where for every HCW vaccinated against influenza, a polio vaccine is donated through UNICEF for children in developing nations. It also analyses the efficacy and cost of the campaign. METHOD: This observational prospective non-randomized cohort study was conducted across 262 PCCs and 15.812 HCWs. A total of 42 PCCs were delivered the full campaign, 114 were used as the control group, and 106 were excluded. The vaccine uptake in HCWs within each of those PCCs was registered. The cost analysis assumes that campaign costs remain stable year to year, and the only added cost would be the polio vaccines (0.59€). RESULTS: We found statistically significant differences between both groups. A total of 1423 (59.02%) HCWs got vaccinated in the intervention group and 3768 (55.76%) in the control group OR 1.14, CI 95% (1.04-1.26). In this scenario, each additional HCW vaccinated in the intervention group costs 10.67€. Assuming all 262 PCCs had joined the campaign and reached 59.02% uptake, the cost of running this incentive would have been 5506€. The potential cost of increasing uptake in HCWs by 1% across all PCC (n = 8816) would be 1683€, and across all healthcare providers, 8862€ (n = 83.226). CONCLUSIONS: This study reveals that influenza vaccination uptake can be innovative by including solidary incentives and be successful in increasing uptake in HCWs. The cost of running a campaign such as this one is low.

[Public funding impact of the pneumococcal vaccine on compliance with the vaccination schedule.] / Impacto de la financiación pública de la vacuna frente a neumococo en el cumplimiento de la pauta vacunal.

OBJECTIVE: It is important to know the impact of public financing on routine vaccination on compliance with the vaccination regimen. Few studies have been carried out on this topic. The objective of this study was to describe the effect of public financing of pneumococcal vaccine on vaccination coverage and the degree of compliance with the vaccination regimen in the child population of the Community of Madrid (CM). METHODS: A descriptive observational study was carried out. The study population were children vaccinated in the period of public (2008 and 2010) and private (2012 and 2013) funding. Data source was the vaccination information system. We estimated the coverage of "full inmunization" at 24 months and the coverage of "vaccination on time" of the primary vaccination and the complete schedule. Comparison according to the type of financing was made using the prevalence ratio (PR) and the relative percentage of change. The delay between vaccine doses was calculated at 24 months of age. RESULTS: On-time vaccination coverage was 72% when public financing of the vaccine and 64% when private financing (PR= 1.12). The delay between doses was greater than 10% when funding was private. CONCLUSIONS: Public financing of the vaccine improves compliance with the vaccine regimen.

OBJETIVO: Es importante conocer el impacto de la financiación pública de la vacunación sistemática sobre el cumplimiento de la pauta vacunal. Se han realizado pocos estudios sobre este tema. El objetivo de este estudio fue describir el efecto de la financiación pública de la vacuna antineumocócica sobre la cobertura de vacunación y el grado de cumplimiento de la pauta vacunal en la población infantil de la Comunidad de Madrid (CM). METODOS: Se realizó un estudio observacional descriptivo. La población de estudio fueron niños residentes en la Comunidad de Madrid que alcanzaron la edad de vacunación en los períodos de financiación pública (2008 y 2010) y privada (2012 y 2013). La fuente de datos fue el sistema de información vacunal de la CM. Se estimó la cobertura de "vacunación completa" a los 24 meses y la cobertura de "vacunación a tiempo" de la primovacunación y de la pauta completa. La comparación según el tipo de financiación se efectuó mediante la razón de prevalencias (RP) y el porcentaje relativo del cambio. Se calculó el retraso entre dosis vacunales a los veinticuatro meses de edad. RESULTADOS: La cobertura de vacunación a tiempo fue del 72% cuando la financiación de la vacuna fue pública y del 64% cuando fue privada (RP=1,12). El retraso entre dosis fue mayor del 10% cuando la financiación fue privada. CONCLUSIONES: La financiación pública de la vacuna mejora el cumplimiento de la pauta vacunal.

[Evaluation of a meningococcal ACWY catch-up vaccination program for adolescents on Community of Madrid.] / Evaluación de la vacunación de rescate frente a meningococo ACWY en adolescentes de la Comunidad de Madrid.

OBJECTIVE: In 2019 the Interterritorial Board of the Spanish National Health System approved the modification of the vaccination strategy against meningococcus. The objective of this study was to evaluate the meningococcal ACWY catch-up vaccination program in adolescents born in 2001 and 2002 in the Community of Madrid. METHODS: Cross-sectional population-based study. Vaccine coverage was estimated and factors associated with vaccination were assessed using logistic regression models. RESULTS: Vaccination coverage was 57.1% for those born in 2001 and 51.9% for those born in 2002. The probability of vaccination was higher in women (ORa=1.18), adolescents with chronic conditions (ORa=1.38), residents in rural areas (ORa=1.76) and in areas with lower socioeconomic level. Being born in 2002 (ORa=0.78) and abroad (ORa=0.35) were associated with a lower probability of vaccination. CONCLUSIONS: Coverage is high compared to similar campaigns in other settings, although there is significant room for improvement, so our study can contribute to the design of strategies to optimize results.

OBJETIVO: En 2019, el Consejo Interterritorial del Sistema Nacional de Salud aprobó la modificación de la estrategia de vacunación frente a meningococo. El objetivo de este estudio fue evaluar la vacunación de rescate frente a meningococo A, C, W, Y en adolescentes nacidos en 2001 y 2002 en la Comunidad de Madrid. METODOS: Se realizó un estudio transversal de base poblacional. Se determinó la cobertura vacunal y los factores asociados a la vacunación, utilizando modelos de regresión logística. RESULTADOS: La cobertura vacunal fue del 57,1% para nacidos en 2001 y del 51,9% para nacidos en 2002. La probabilidad de vacunación fue mayor en mujeres (ORa=1,18), adolescentes con alguna enfermedad crónica (ORa=1,38), residentes en el ámbito rural (ORa=1,76) y en zonas con menor nivel socioeconómico. Haber nacido en 2002 (ORa=0,78) y en el extranjero (ORa=0,35) se asociaron a una menor probabilidad de vacunación. CONCLUSIONES: La cobertura es elevada en comparación con campañas similares en otros entornos, aunque existe un importante margen de mejora, por lo que nuestro estudio puede contribuir al diseño de estrategias para optimizar los resultados.