Evaluación de la efectividad de la vacuna antigripal: diseño de casos confirmados por laboratorio y controles negativos a gripe

La realización de esta tesis ha sido posible gracias a la financiación obtenida en diversas convocatorias competitivas de fondos públicos que se detallan a continuación: Ministerio de Sanidad, Servicios Sociales e Igualdad (EC11-302), Instituto de Salud Carlos III (GR09/0028, PS09/01179 y PS12/00087) y Programa I-MOVE (Influenza Monitoring Vaccine Effectiveness in Europe) financiado por el ECDC (European Centre for Disease Prevention and Control).El objetivo de esta tesis es evaluar la efectividad de la vacuna (EV) de la gripe en la prevención de casos confirmados por laboratorio en Navarra durante las temporadas de gripe 2010-2011, 2011-2012 y 2012-2013, analizar la variabilidad del efecto de la vacuna dentro de cada temporada y evaluar aspectos metodológicos que afectan al diseño de casos y controles negativos. La vacuna antigripal presenta en promedio un efecto protector moderado para prevenir casos de gripe confirmados, aunque la EV puede variar de unas temporadas a otras, por lo que es necesario continuar evaluando cada año la EV frente a la gripe. No se observaron diferencias en la EV frente a casos ambulatorios y hospitalizados. La selección de pacientes con criterio sistemático puede sesgar ligeramente los resultados. Los protocolos de vigilancia de la gripe deberían limitar la toma de frotis a los primeros días tras el inicio de los síntomas, para evitar incluir falsos negativos.The aims were to evaluate the influenza VE in preventing laboratory-confirmed cases in Navarra during the influenza seasons 2010-2011, 2011-2012 and 2012-2013, to analyze the changes of the VE during each season and to evaluate the influence of some methodological aspects in the estimation of VE. Influenza vaccine has on average a moderate protective effect in preventing laboratory-confirmed influenza, although VE may widely vary from season to season, so it is necessary to continue evaluating the influenza VE every year. VE did not show differences between hospitalized and primary healthcare patients. Systematic selection of patients for swabbing may bias the results. Furthermore, influenza surveillance protocols should limit swabbing to patients in the first days after the symptom onset to prevent false negative results.Ministerio de Sanidad, Servicios Sociales e Igualdad Instituto de Salud Carlos III European Centre for Disease Prevention and Control (ECDC)Programa de Doctorado en Ciencias de la Salud (RD 99/2011)Osasun Zientzietako Doktoretza Programa (ED 99/2011

Respiratory syncytial virus hospitalization in children in northern Spain

Objectives: Understanding respiratory syncytial virus (RSV) morbidity may help to plan health care and future vaccine recommendations. We aim to describe the characteristics and temporal distribution of children diagnosed with RSV admitted in a Spanish hospital. Methods: Descriptive study for which the hospital discharges of children < 5 years of age with RSV infection were analyzed. The information was extracted from the hospital discharge database of a reference pediatric hospital in northern Spain for the 2010-2011 to 2014-2015 RSV seasons. Results: Six hundred and forty-seven hospitalizations of children with RSV infection were analyzed, 94% of which occurred between the second week of November and the last week of March. Most children (72%) were under one year of age and 95% were previously healthy infants. Infants born from October to December had the highest risk of hospitalization in the first year of life. The median length of hospital stay of children with and without comorbidities was six and three days, respectively. 6.5% of the hospitalized cases were admitted to the pediatric intensive care unit; this percentage was higher among children < 2 months (adjusted odds ratio 4.15; 95% confidence interval: 1.37-12.61) or with comorbidities (adjusted odds ratio 4.15; 95% confidence interval: 1.53-11.28). The case lethality was 0.3%. Conclusions: The risk of hospitalizations for RSV is high during the first year of life and increases among infants born in the fall. Being under two months of age and presenting comorbidities are the main risk factors associated to pediatric intensive care unit admission

Combined effectiveness of prior and current season influenza vaccination in northern Spain: 2016/17 mid-season analysis

The 2016/17 mid-season vaccine effectiveness estimate against influenza A(H3N2) was 15% (95% confidence interval: -11 to 35) in Navarre. Comparing to individuals unvaccinated in the current and four prior seasons, effectiveness was 24% for current and 3-4 prior doses, 61% for current and 1-2 prior doses, 42% for only current vaccination, and 58% for 3-4 prior doses. This suggests moderate effectiveness for different combinations of vaccination in the current and prior seasons.This study was supported by the Horizon 2020 program of the European Commission (agreement 634446); by the I-MOVE (Influenza Monitoring Vaccine Effectiveness in Europe) Network funded by the European Centre for Disease Prevention and Control; by La Caixa Foundation; and by the Carlos III Institute of Health with the European Regional Development Fund (ERDF) (CM15/00119, INT15/00182).S

Effectiveness of influenza vaccination in preventing influenza in primary care, Navarre, Spain, 2021/22

Compared with individuals unvaccinated in the current and three previous influenza seasons, in 2021/22, influenza vaccine effectiveness at primary care level was 37% (95% CI: 16 to 52) for current season vaccination, regardless of previous doses, and 35% (95% CI: -3 to 45) for only previous seasons vaccination. Against influenza A(H3N2), estimates were 39% (95% CI: 16 to 55) and 24% (95% CI: -8 to 47) suggesting moderate effectiveness of current season vaccination and possible remaining effect of prior vaccinations.This study was supported by the Influenza Monitoring Vaccine Effectiveness in Europe (I-MOVE) Network funded by the European Centre for Disease Prevention and Control (RS/2021/DRP/12984) and by the Instituto de Salud Carlos III with the European Regional Development Fund (PI20/01323, CM19/00154, and INT21/00100).S

Monitoring COVID‐19 vaccine effectiveness against COVID‐19 hospitalisation and death using electronic health registries in ≥65 years old population in six European countries, October 2021 to November 2022

Background: Within the ECDC-VEBIS project, we prospectively monitored vaccine effectiveness (VE) against COVID-19 hospitalisation and COVID-19-related death using electronic health registries (EHR), between October 2021 and November 2022, in community-dwelling residents aged 65-79 and ≥80 years in six European countries. Methods: EHR linkage was used to construct population cohorts in Belgium, Denmark, Luxembourg, Navarre (Spain), Norway and Portugal. Using a common protocol, for each outcome, VE was estimated monthly over 8-week follow-up periods, allowing 1 month-lag for data consolidation. Cox proportional-hazards models were used to estimate adjusted hazard ratios (aHR) and VE = (1 - aHR) × 100%. Site-specific estimates were pooled using random-effects meta-analysis. Results: For ≥80 years, considering unvaccinated as the reference, VE against COVID-19 hospitalisation decreased from 66.9% (95% CI: 60.1; 72.6) to 36.1% (95% CI: -27.3; 67.9) for the primary vaccination and from 95.6% (95% CI: 88.0; 98.4) to 67.7% (95% CI: 45.9; 80.8) for the first booster. Similar trends were observed for 65-79 years. The second booster VE against hospitalisation ranged between 82.0% (95% CI: 75.9; 87.0) and 83.9% (95% CI: 77.7; 88.4) for the ≥80 years and between 39.3% (95% CI: -3.9; 64.5) and 80.6% (95% CI: 67.2; 88.5) for 65-79 years. The first booster VE against COVID-19-related death declined over time for both age groups, while the second booster VE against death remained above 80% for the ≥80 years. Conclusions: Successive vaccine boosters played a relevant role in maintaining protection against COVID-19 hospitalisation and death, in the context of decreasing VE over time. Multicountry data from EHR facilitate robust near-real-time VE monitoring in the EU/EEA and support public health decision-making.European Centre for Disease Prevention and Control, Grant/Award Numbers ECDC/2021/018, RS/2022/DTS/24104.info:eu-repo/semantics/publishedVersio

Health and economic impact of seasonal influenza mass vaccination strategies in European settings: A mathematical modelling and cost-effectiveness analysis

Free PMC article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8861572/Introduction: Despite seasonal influenza vaccination programmes in most countries targeting individuals aged ≥ 65 (or ≥ 55) years and high risk-groups, significant disease burden remains. We explored the impact and cost-effectiveness of 27 vaccination programmes targeting the elderly and/or children in eight European settings (n = 205.8 million). Methods: We used an age-structured dynamic-transmission model to infer age- and (sub-)type-specific seasonal influenza virus infections calibrated to England, France, Ireland, Navarra, The Netherlands, Portugal, Scotland, and Spain between 2010/11 and 2017/18. The base-case vaccination scenario consisted of non-adjuvanted, non-high dose trivalent vaccines (TV) and no universal paediatric vaccination. We explored i) moving the elderly to "improved" (i.e., adjuvanted or high-dose) trivalent vaccines (iTV) or non-adjuvanted non-high-dose quadrivalent vaccines (QV); ii) adopting mass paediatric vaccination with TV or QV; and iii) combining the elderly and paediatric strategies. We estimated setting-specific costs and quality-adjusted life years (QALYs) gained from the healthcare perspective, and discounted QALYs at 3.0%. Results: In the elderly, the estimated numbers of infection per 100,000 population are reduced by a median of 261.5 (range across settings: 154.4, 475.7) when moving the elderly to iTV and by 150.8 (77.6, 262.3) when moving them to QV. Through indirect protection, adopting mass paediatric programmes with 25% uptake achieves similar reductions in the elderly of 233.6 using TV (range: 58.9, 425.6) or 266.5 using QV (65.7, 477.9), with substantial health gains from averted infections across ages. At €35,000/QALY gained, moving the elderly to iTV plus adopting mass paediatric QV programmes provides the highest mean net benefits and probabilities of being cost-effective in all settings and paediatric coverage levels. Conclusion: Given the direct and indirect protection, and depending on the vaccine prices, model results support a combination of having moved the elderly to an improved vaccine and adopting universal paediatric vaccination programmes across the European settings.Highlights: Seasonal influenza vaccine programmes usually target at-risk and older individuals; We used an age-structured dynamic-transmission model for eight European settings; Older people benefit from adjuvanted or high-dose trivalent or quadrivalent vaccines; Adopting mass paediatric influenza vaccination is also likely to be cost-effective; Results rest on vaccine costs, willingness to vaccinate and unknown long-term effects.I-MOVE+ (Integrated Monitoring of Vaccines in Europe) project, received a grant from the European Commission Horizon 2020 research and innovation programme (grant agreement No 634446).info:eu-repo/semantics/publishedVersio