NBER Working Papers


  • Assessing the Age Specificity of Infection Fatality Rates for COVID-19: Meta-Analysis & Public Policy Implications

    To assess age-specific infection fatality rates (IFRs) for COVID-19, we have conducted a systematic review of #seroprevalence studies as well as countries with comprehensive tracing programs.

    Age-specific IFRs were computed using the prevalence data in conjunction with reported fatalities four weeks after the midpoint date of each study, reflecting typical lags in fatalities and reporting.

    Using metaregression procedures, we find a highly significant log-linear relationship between age and IFR for COVID-19. The estimated age-specific IFRs are very low for children and younger adults but increase progressively to 0.4% at age 55, 1.3% at age 65, 4.2% at age 75, and 14% at age 85.

    About 90% of the geographical variation in population IFR is explained by differences in age composition of the population and age-specific prevalence.

    These results indicate that COVID-19 is hazardous not only for the elderly but also for middle-aged adults. Moreover, the population IFR for #COVID-19 should not be viewed as a fixed parameter but as intrinsically linked to the age-specific pattern of infections. Consequently, public health measures to protect vulnerable age groups could substantially decrease total deaths.

    #IFR #mortalité

  • The Effects of Immigration on the Economy: Lessons from the 1920s Border Closure

    In the 1920s, the United States substantially reduced immigrant entry by imposing country-specific quotas. We compare local labor markets with more or less exposure to the national quotas due to differences in initial immigrant settlement. A puzzle emerges: the earnings of existing US-born workers declined after the border closure, despite the loss of immigrant labor supply. We find that more skilled US-born workers – along with unrestricted immigrants from Mexico and Canada – moved into affected urban areas, completely replacing European immigrants. By contrast, the loss of immigrant workers encouraged farmers to shift toward capital-intensive agriculture and discouraged entry from unrestricted workers.

    #fermeture_des_frontières #migrations #économie #histoire #USA #Etats-Unis #travail #marché_du_travail