The Burden of Early Exposure to Malaria in the United States, 1850-1860: Malnutrition and Immune Disorders

Race, immunity, and lifespan: Unraveling the effect of early-life exposure to malaria risk on lifespan

We investigate a historical experience to measure the long-term effect of malaria on lifespan among infected survivors and identify a factor that mitigates malaria's effect. Using a sample of Union Army veterans born during the mid-19th century and their lifetime records, we show that exposure to high risk of malaria at birth or in early life substantially shortened their lifespan. The legacy of exposure to malaria is robust while controlling for lifetime socioeconomic and health conditions, fixed effects, and considering selection bias. Additionally, we include the US Colored Troops sample of black veterans to analyze racial differences in the effect of malaria exposure on lifespan. Exposure to malaria did not lead to a shorter lifespan among black veterans. Evidence suggests that genetic immunity to malaria in black veterans might contribute this heterogeneity.

Pathogen prospecting of museums: Reconstructing malaria epidemiology

Malaria is a disease of global significance. Ongoing changes to the earth's climate, antimalarial resistance, insecticide resistance, and socioeconomic decline test the resilience of malaria prevention programs. Museum insect specimens present an untapped resource for studying vector-borne pathogens, spurring the question: Do historical mosquito collections contain Plasmodium DNA, and, if so, can museum specimens be used to reconstruct the historical epidemiology of malaria? In this Perspective, we explore molecular techniques practical to pathogen prospecting, which, more broadly, we define as the science of screening entomological museum specimens for human, animal, or plant pathogens. Historical DNA and pathogen prospecting provide a means of describing the coevolution of human, vector, and parasite, informing the development of insecticides, diagnostics, therapeutics, and vaccines.

Wrong place, wrong time: The long-run effects of in-utero exposure to malaria on educational attainment

This paper investigates the long-term relationship between early life exposure to malaria and human capital accumulation in Brazil. The identification strategy relies on exogenous variation in the risk of malaria outbreaks in different states and seasons of the year to identify in utero exposure according to the timing and location of birth. I find consistent negative treatment effects of in utero exposure to malaria on educational attainment. The effects are stronger for exposure during the first trimester of pregnancy than during other periods of gestation. Effective anti-malaria policies can, thus, be an important factor contributing to reducing the educational inequality by targeting pregnant women, especially those in their first months of gestation.

Early life adversity, biological adaptation, and human capital: evidence from an interrupted malaria control program in Zambia

Growing evidence from evolutionary biology demonstrates how early life shocks trigger physiological changes designed to be adaptive in challenging environments. We examine the implications of one type of physiological adaptation - immunity formation - for human capital accumulation. Using variation in early life malaria risk generated by an interrupted disease control program in Zambia, we show that exposure to infectious diseases during the first two years of life can reduce the harmful effects of malaria exposure on cognitive development during the preschool years. These findings suggest a non-linear and trajectory-dependent relationship between early life adversity and human capital formation.

Syndemics and the history of disease: Towards a new engagement

Historians of medicine and disease have yet to think through a syndemic lens. This commentary aims to point out why they should. Although there are several hurdles to overcome, our histories of disease and our understanding of current syndemics both stand to gain should historians begin to explore episodes of cooccurring diseases that share root causes.

Malaria and Lyme disease - the largest vector-borne US epidemics in the last 100 years: success and failure of public health

Malaria and Lyme disease were the largest vector-borne epidemics in recent US history. Malaria, a mosquito-borne disease with intense transmission, had higher morbidity and mortality, whereas Lyme and other tick-borne diseases are more persistent in the environment. The responses to these two epidemics were markedly different. The anti-malaria campaign involved large-scale public works eradicating the disease within two decades. In contrast, Lyme disease control and prevention focused on the individual, advocating personal protection and backyard control, with the disease incidence steeply increasing since 1980s. Control of Lyme and other tick-borne diseases will require a paradigm shift emphasizing measures to reduce tick and host (deer) populations and a substantial R&D effort. These steps will require changing the political climate, perceptions and opinions to generate support among governmental levels and the general public. Such support is essential for providing a real solution to one of the most intractable contemporary public health problems.

Long-term impacts of early-life exposure to malaria: Evidence from Taiwan's Eradication Campaign in the 1950s

This paper utilizes the eradication campaign in Taiwan in the 1950s to estimate the long-term impacts of early-life (in utero and postnatal) exposure to malaria. Matching adults in the 1992-2012 Taiwan Social Change Survey to the malaria intensity in their individual place and year of birth, difference-in-difference estimation shows strong evidence that the eradication increased men's own educational attainment as well as their family income in adulthood. We also use the 1980 census data to show there was a sharp education increase after the eradication. Furthermore, the eradication increased the educational attainment of married men's spouses. Finally, quantile regressions show that the effect concentrated on the lower percentile of the income distribution. Overall, our results suggest negative effects of early-life exposure to malaria.

Growth and maturity: A quantitative systematic review and network analysis in anthropometric history

This paper reviews the current wealth of anthropometric history since the early efforts of Robert Fogel in the 1970s. The survey is based on a quantitative systematic review of the literature and counts a total of 447 peer-reviewed articles being published in the main leading journals in economic history, economics and biology. Data are analysed using network analysis by journal and author and the main contributions of anthropometric history are highlighted, pointing to future areas of inquiry. The contributions of books and book chapters are also quantified and analysed.

Adapting to the Weather: Lessons from U.S. History

An important unknown in understanding the impact of climate change is the scope of adaptation, which requires observations on historical time scales. We consider how weather across U.S. history (1860-2000) has affected various measures of productivity. Using cross-sectional and panel methods, we document significant responses of agricultural and individual productivity to weather. We find strong effects of hotter and wetter weather early in U.S. history, but these effects have been attenuated in recent decades. The results suggest that estimates from a given period may be of limited use in forecasting the longer-term impacts of climate change.

Union Army Veterans, All Grown Up

This paper overviews the research opportunities made possible by a NIA-funded program project, Early Indicators, Intergenerational Processes, and Aging. Data collection began almost three decades ago on 40,000 soldiers from the Union Army in the US Civil War. The sample contains extensive demographic, economic, and medical data from childhood to death. In recent years, a large sample of African-American soldiers and an oversampling of soldiers from major US cities have been added. Hundreds of historical maps containing public health data have been geocoded to place soldiers and their family members in a geospatial context. With newly granted funding, thousands of veterans will be linked to the demographic information available from the census and vital records of their children.

Health and the Economy in the United States, from 1750 to the Present

I discuss the health transition in the United States, bringing new data to bear on health indicators, and investigating the changing relationship between health, income, and the environment. I argue that scientific advances played an outsize role and that health improvements were largest among the poor. Health improvements were not a precondition for modern economic growth. The gains to health are largest when the economy has moved from "brawn" to "brains" because this is when the wage returns to education are high, leading the healthy to obtain more education. More education may improve use of health knowledge, producing a virtuous cycle.

Learning, Misallocation, and Technology Adoption: Evidence from New Malaria Therapy in Tanzania

I study how the misallocation of new technology to individuals who have low ex post returns to its use affects learning and adoption behavior. I focus on antimalarial treatment, which is frequently over-prescribed in many low-income country contexts where diagnostic tests are inaccessible. I show that misdiagnosis reduces average therapeutic effectiveness, because only a fraction of adopters actually have malaria, and slows the rate of social learning due to increased noise. I use data on adoption choices, the timing and duration of fever episodes, and individual blood slide confirmations of malarial status from a pilot study for a new malaria therapy in Tanzania to show that individuals whose reference groups experienced fewer misdiagnoses exhibited stronger learning effects and were more likely to adopt.

Malaria: an early indicator of later disease and work level

This study investigates the effect of early-life exposure to malaria on disease and work level in old age over the past one and a half centuries. Using longitudinal lifetime records of Union Army veterans, I first estimate that exposure to a malarial environment in early life (c.1840) substantially increased the likelihood of having various chronic diseases and not working in old age (c.1900). Second, from data on US cohorts born between 1891 and 1960, I find that those exposed to a higher level of the anti-malaria campaign, which began in 1921, had lower levels of work disability in old age. Third, I seek the same implications for the modern period by linking WHO's country statistics on DALYs among older populations in 2004 to country-level malaria risk in pre-eradication era. In the paper, I discuss possible mechanisms and propose the significance of malaria eradication and early-life conditions from a long-term perspective.

Height and death in the Antebellum United States: A view through the lens of geographically weighted regression

Factors related to geography such as climate, natural resources or waterways often affect human activities. However, traditional approaches such as ordinary least squares (OLS) have limitations in investigating such patterns. Unlike OLS regression, geographically weighted regression (GWR) allows the coefficients of explanatory variables to differ by locality by giving relatively more weight to geographically close observations. GWR depicts spatial patterns. This paper examines the pattern of height and crude death rate in the United States prior to the Civil War by this method. The GWR results show that access to water transportation increased mortality and decreased stature in the food exporting areas of the Midwest, and the opposite pattern appeared in the food importing areas of the Northeast.

Survival in 19th Century Cities: The Larger the City, the Smaller Your Chances

Using Union Army veterans' lifetime socioeconomic and health records, this essay finds a consistent and persistent hierarchy in survival rates and hazard ratios by urban size at and across three stages of life: birth, late adolescence, and death. This urban mortality penalty remains after controlling for variables associated with each individual veteran. The results of our geographical mobility analyses suggest that, with respect to these veterans, the search for an explanation should focus on late adolescence and adulthood as much as on early life. A complete explanation of the penalty requires a project of greater scope.