Epidemiological Transitions in Influenza Dynamics in the United States: Insights from Recent Pandemic Challenges

The SARS-CoV-2 pandemic has reshaped the epidemiological landscape of respiratory diseases, with profound implications for seasonal influenza. Nonpharmaceutical interventions implemented globally during the pandemic significantly altered human behavior and reduced the prevalence of respiratory pathogens, including influenza. However, the post-pandemic resurgence of influenza activity to pre-pandemic levels highlights the persistent challenges posed by this virus. During the 2023–2024 influenza season in the United States, an estimated 40 million individuals contracted influenza, resulting in 470,000 hospitalizations and 28,000 deaths, with the elderly disproportionately affected. Pediatric mortality was also notable, with 724 deaths reported among children. This study examines trends in influenza incidence, vaccination rates, and mortality in the United States from the 2018–2019 through to the 2023–2024 influenza seasons. Additionally, it evaluates the interplay between influenza and SARS-CoV-2 during the pandemic, considering the impact of disrupted air travel, public health measures, and altered virus circulation dynamics. By integrating these insights, the study underscores the critical need for sustained vaccination campaigns and innovative public health strategies to mitigate the dual burden of respiratory diseases. Findings from this analysis highlight the urgency of strengthening prevention and surveillance systems to enhance pandemic preparedness and reduce the impact of respiratory pathogens in an evolving epidemiological landscape.