A tale of three pandemics: Impacts on life expectancy and lifespan inequality

This study aims to provide a comparative analysis of the impacts of three significant pandemics - the 1918-19 influenza pandemic, the HIV/AIDS epidemic, and the COVID-19 pandemic - on life expectancy and lifespan inequality. Using cause-eliminated life tables and the Theil Index, we examine changes in life expectancy and lifespan inequality globally. The findings reveal that each pandemic uniquely altered demographic patterns. The 1918 influenza pandemic caused the sharpest immediate reductions in life expectancy, particularly affecting young adults, and led to a significant rise in lifespan inequality. In contrast, the HIV/AIDS epidemic had a more gradual and enduring impact, disproportionately affecting young and middle-aged adults in its early stages and exacerbating health disparities, especially in regions with limited access to antiretroviral therapy. COVID-19 primarily impacted older populations, resulting in smaller reductions in life expectancy compared to the 1918 influenza but with a distinctive decrease in lifespan inequality due to concentrated mortality among older adults. Furthermore, gender-specific effects varied across the pandemics. While the 1918 influenza pandemic and COVID-19 showed relatively uniform impacts across genders, HIV/AIDS revealed pronounced disparities, with women experiencing greater reductions in life expectancy and heightened lifespan inequality. By examining the unique mortality patterns and impacts of these pandemics, this study provides valuable insights to policymakers, emphasizing the need for tailored public health strategies to address inequalities and improve resilience in future global health crises.