Reevaluating the Long-Term Impact of In Utero Exposure to the 1918 Influenza Pandemic

Area of Science:

• Epidemiology
• Economics
• Public Health

Background:

• Previous research suggested prenatal exposure to the 1918 influenza pandemic negatively affected adult socioeconomic status (SES).
• The identification strategy of prior studies relied on cohort comparisons, potentially overlooking confounding factors like family background.

Purpose of the Study:

• To re-examine the long-term socioeconomic consequences of in utero exposure to the 1918 influenza pandemic.
• To assess the robustness of previous findings using alternative methodologies and data.

Main Methods:

• Utilized census data to analyze the adult SES of the 1919 birth cohort exposed in utero to the 1918 influenza pandemic.
• Employed household fixed effects models and replicated state-level dose-response analyses.
• Conducted city-level analyses on educational attainment using World War II enlistee data.

Main Results:

• The 1919 birth cohort originated from lower-SES families, challenging the cohort-comparison approach.
• The estimated adult SES deficit diminished substantially when controlling for background characteristics and became statistically insignificant with household fixed effects.
• State-level analyses of census data revealed no significant impact of influenza exposure on adult SES.
• City-level analyses on educational attainment yielded mixed results.

Conclusions:

• The purported link between prenatal exposure to the 1918 influenza pandemic and reduced adult SES is not supported by this analysis.
• Methodological limitations in previous studies may have overestimated the pandemic's long-term socioeconomic effects.
• Further research is needed to clarify the complex relationship between infectious disease exposure and socioeconomic outcomes.