The long term impact of the 1918 influenza pandemic in Norway

Abstract

A growing literature show the negative effect of prenatal health shocks on childhood and adult outcomes. Several studies exploit disease outbreaks to find causal effects of in utero exposure on various outcomes. We build on the existing literature by applying theories of in utero health effects to Norwegian data. This thesis uses the 1918 Spanish Influenza pandemic as a natural experiment to investigate the impact of prenatal health shock on various long term outcomes in Norway. Influenza is considered a negative shock to the intrauterine environment, and has been shown to lower both cognitive and non-cognitive abilities. We use unique historical data provided by Statistics Norway that contains information on the Influenza mortality and morbidity rate, the number of still births and population estimates from 1912 to 1919. In addition, we have collected data from the Statistical Bulletin which provides information on tax income in all municipalities. This data is matched to the 1960 census, allowing us to estimate effects on year of education, marital status, number of children and employment status. We find that exposure to prenatal Influenza leads to a reduction in years of education for men. This effect is twice as large for the poorest municipalities in Norway, indicating that negative shocks are more severe for the lower socioeconomic groups. Since early intervention is far more bene_cial for both social and economic outcomes, than interventions later in life, measures to prevent these serious implications are relatively cheap and easily attainable, and should be offered to all pregnant women.