Abstract
Abstract
Background and Objectives
Influenza vaccination has a strong safety record and is effective in reducing pediatric influenza-associated morbidity and mortality. However, pediatric vaccination coverage (VC) has declined since the 2019/20 influenza season in the United States. We estimated the impact of increased vaccine protection (through increased VC and/or vaccine effectiveness [VE]) on pediatric influenza-associated burden during the 2022/23–2024/25 seasons.
Methods
We used a compartmental model and laboratory-confirmed influenza-associated hospitalization, VC, and VE data among children 6 months–17 years to estimate influenza burden from 2022/23–2024/25 (the ‘baseline’ scenario) and the impact of vaccination. We simulated scenarios that (1) increased VC by five percentage points; (2) increased VE by five percentage points; (3) increased VC and VE by five percentage points; and (4) increased VC to levels achieved in 2019/20 (the season with the highest pediatric VC to date). We estimated the difference in hospitalizations and deaths between each scenario and the baseline scenario.
Results
Among children 6 months–17 years, an estimated 120,000 influenza-associated hospitalizations and 1,650 deaths occurred across all seasons at baseline. Increasing VC to 2019/20 levels had the greatest estimated impact, reducing hospitalizations by 8,670 (7.2%) and deaths by 130 (7.9%). Increasing both VC and VE by five percentage points reduced hospitalizations by 6.6% and deaths by 6.7%, whereas increasing VC or VE by five percentage points reduced hospitalizations by 3.1% and deaths by 3.2%.
Conclusions
Increasing pediatric influenza vaccination coverage back to 2019/20 levels was estimated to significantly reduce pediatric influenza-associated morbidity and mortality.
What’s known on this subject
Pediatric influenza vaccination coverage has declined in the United States since the 2019/20 influenza season despite its effectiveness and strong safety record. The impact of this decline on influenza-associated morbidity and mortality has not been quantified.
What this study adds
We estimated pediatric influenza-associated outcomes in the 2022/23–2024/25 influenza seasons under different scenarios that increased vaccination coverage and/or effectiveness. We estimated the greatest reductions in influenza-associated hospitalizations and deaths (7.2% and 7.9%, respectively) if coverage remained at 2019/20 levels.