Long-Term Effects of in-Utero Exposure to the 1918 Influenza Pandemic: The Case of Longevity

Won-tak Joo, University of Florida
Sam Hwang, University of British Columbia

Studies of the 1918 Spanish flu show a higher risk of disability and chronic disease among those exposed to the pandemic in utero, suggesting that disruption in fetal development may leave permanent damage on the physiological system. We test this hypothesis using complete mortality records from FamilySearch genealogy data linked to the decennial censuses. We address methodological limitations of previous studies in two ways. First, using rich information on family relationships, we adjust for selective births during the pandemic period by controlling for parents’ longevity or using family fixed effects. Second, using mortality statistics from the Census Bureau, we reconstruct monthly patterns of period mortality during the 1918 pandemic and re-estimate longevity effects using exposure weighted by city-level excess mortality. These findings will enhance our understanding of the population consequences of the 1918 Spanish flu and suggest implications for the long-term consequences of COVID-19 and future pandemics.

No extended abstract or paper available

 Presented in Session 14. Mortality: The Aftermath of Disease