Marcella Alsan always knew she wanted to be a doctor when she grew up. Being an economist at the same time was not part of the plan.
But during medical school, Alsan worked at a public hospital in Quito, Ecuador, an institution so poor that doctors had to send patients to the pharmacy down the street to buy their own bandages and syringes. One day, a 9-year-old girl hit by a bus was brought to the hospital, and Alsan, who didn’t have the equipment for a blood transfusion, was unable to save her.
Alsan began to think about the root causes of death and disease, and realized that if she really wanted to make a difference, she needed to know more than how to treat an individual patient with medicine. She needed to understand how social forces affect a population’s health.
Now Alsan, who recently completed her PhD in economics at Harvard University, may have solved a puzzle that has befuddled scholars, development specialists, and policy makers: Why is the land-abundant, resource-rich continent of Africa so poor?
The answer comes out of Alsan’s graduate school research on the tsetse fly’s effect on poverty in Africa. Using geospatial mapping software to mine data gathered by missionaries and anthropologists in the 1800s, Alsan found that the fly, which exists only in Africa and is lethal to livestock, drove precolonial Africans to use slaves instead of domesticated animals for agriculture.
That greatly limited their crop yields and ability to transport goods. Farming methods such as using plows, wheelbarrows, and manure — which grew from using animals in other countries — were not widely adopted in Africa, which instead relied on less effective slash-and-burn techniques. All of this limited the population because the continent wasn’t able to produce vast quantities of food to support more people.
And all because of a pesky fly.
“Africa didn’t go down this development path for no reason,” said Alsan, 36.
Harvard economics professor Claudia Goldin, one of Alsan’s advisers, called the work on the tsetse fly an important breakthrough.
“It’s an extremely rich piece of work,” Goldin said. “A historian would say it’s now a more nuanced view of climate and geography and disease and slavery.”
Alsan grew up in Naperville, Ill., the youngest daughter of a vascular surgeon and a hospital administrator turned homemaker. “My sisters were always grossed out by blood, and I would go and find dead birds in the chimney and want to dissect them,” she said.
As an undergraduate, Alsan majored in biology and psychology at Harvard. She then earned a medical degree from Loyola University Chicago, followed by a master’s in public health from Harvard.
The book “Infections and Inequalities” by Paul Farmer, founder of the Boston-based global health nonprofit Partners in Health, was a big influence on Alsan, who cites Farmer’s focus on how “large scale social forces affect the distribution and outcome of disease” as a driving force in her work.
Farmer, with whom Alsan authored a paper about poverty and disease in Haiti and Rwanda, is equally complimentary. In a letter to a Harvard fellowship committee, Farmer said Alsan’s tsetse fly research “constructs a novel data set that opens many new doors in the study of the economic development of Africa over time.”
Alsan finds great satisfaction in being a physician economist. Seeing patients, which she continued to do as an infectious disease fellow at Massachusetts General Hospital while she studied for her PhD, gave her the satisfaction of helping people while grinding through years of economic research. She will continue to see patients at the Stanford School of Medicine, where she begins a job as an assistant professor of health policy in the fall.
Alsan, the mother of two, sees children’s health as the next phase of her work. She has been researching the effects of a mass immunization effort in Turkey that increased vaccination rates from 30 to 85 percent in 1985. The goal, to reduce infant mortality, was not achieved, she found, but there were other interesting results.
For those who were vaccinated, disability rates decreased and height and literacy rates increased. Even those who lived in the same household as a child under 5 who was vaccinated experienced positive spillover effects. The older sisters of vaccinated children seemed to get more education than those of nonvaccinated siblings, presumably because they didn’t have to stay home from school as often to care for a sick sibling.
Alsan plans to keep observing the effects of the vaccination campaign by dissecting Turkish census data. Ultimately, she hopes to show the economic impact of early childhood intervention as it relates to children’s ability to contribute to society later in life. As she has been finding, keeping a child healthy can also have a positive effect on the entire household.
“Marcy is pretty special. She’s even more special than all of her degrees would indicate,” said Goldin. Her work “could not have been done by your run-of-the-mill brilliant economist.”