Moving Target: Epidemiologist Tracks Diseases in Developing Countries

Posted: March 29, 2010 at 1:00 am, Last Updated: March 26, 2010 at 2:29 pm

By Marjorie Musick

Kathryn Jacobsen. Creative Services photo

Around the world, people currently suffer from diseases that have become distant memories in the United States.

As an epidemiologist, Kathryn Jacobsen, assistant professor in the College of Health and Human Services’ Department of Global and Community Health, uses math and statistics to figure out how these diseases are spreading in the hope of helping to prevent them.

“Surprisingly, the two most common causes of death for children under the age of five worldwide are pneumonia and diarrhea. Together, those two diseases can be blamed for about half of all deaths of children,” says Jacobsen.

“Malaria and measles are also frequently fatal,” she continues. “This is terribly sad because nearly all deaths from these four causes could be prevented.”

An equal passion for numbers and biology led Jacobsen to become an epidemiologist.

“I was looking for a career that would let me combine math and medicine with international work. I had this 100-word description of what I wanted to do in a career, and epidemiology has it all. It’s kind of like being a math detective in that we use numbers to help solve health mysteries.”

Tackling Hepatitis A

One of the puzzles Jacobsen is working to solve relates to the changing epidemiology of hepatitis A virus in transitioning economies.

Jacobsen is an internationally recognized expert on hepatitis A and recently wrote a World Health Organization report on the worldwide prevalence of the disease. Her report is foundational for the next round of the Global Burden of Disease Project, which will quantify the effect of the most devastating diseases affecting populations around the globe.

“Hepatitis A is a little unusual. Public health is improved if kids get it when they’re under the age of six because young children usually have almost no symptoms from infection and they get immunity for life.

“The risk of death increases with age, so children should be exposed to the infection at an early age — either naturally or via vaccination — to prevent them from suffering as adults,” says Jacobsen.

Hepatitis A is common in countries with poor sanitary conditions because the virus is spread through contaminated water and food. Jacobsen says that the disease creates a new set of challenges for transitioning economies where urban and high-income children don’t acquire the virus at home but are exposed to it as soon as they step outside the city limits or the reaches of its sewer system.

This has resulted in many teens and 20-somethings developing acute liver failure because they haven’t had the vaccine or were not exposed to hepatitis A as young children.

“The assumption is that, in low-income countries, hepatitis A is there all the time, but few people die because they contract it when they’re children,” Jacobsen explains.

“Adults who get the disease often develop liver failure and end up in the hospital. That allows us to track those extreme cases, but it is difficult to know how many people are actually affected since many cases go unreported.”

Changing Societies, Shifting Diseases

As an unbiased observer who has traveled widely in search of answers to health questions, Jacobsen feels that governments are getting better at sharing information and that improved communication is making a difference. Photo courtesy of Kathryn Jacobsen

When she’s not teaching courses in epidemiology, research methods and international health ethics, Jacobsen researches the causes and consequences of the health transitions that occur around the world in response to socioeconomic and environmental changes.

“Epidemiologists look at a whole community or maybe a state or a country to find the common health problems within the population.

“We figure out what questions need to be answered, how to get the best data to answer those questions and then how to analyze the data and interpret the results,” says Jacobsen.

Traveling around the world, whether to study influenza in Sierra Leone, tropical infections in Ecuador or childhood nutrition in Costa Rica, inevitably brings investigators face to face with cultural differences.

Jacobsen mitigates these challenges through strong partnerships and a lot of planning.

“It’s really about having partnerships in place ahead of time. There is so much legwork that has to happen long before starting a data collection project. Success depends on local partners who value the project, who can focus research in the right directions and who are committed to seeing a project through to completion,” says Jacobsen.

Communicating Public Health Issues

As an unbiased observer who has traveled widely in search of answers to health questions, Jacobsen feels that governments are getting better at sharing information and that improved communication is making a difference.

“We no longer live in a world where it takes three months by boat to get from one continent to another, and, as we well know, germs don’t recognize national boundaries.

“Modern travel means that if there’s an Ebola outbreak in central Africa, there’s a chance that it’s going to show up somewhere else. Strong communication among governments is more important than ever before,” says Jacobsen.

Blending classroom instruction with real-world experience is a priority for Jacobsen. As much as she enjoys leading research studies, she is equally enthused about teaching. She involves her students in field research and then helps those students get their work into professional journals.

“A lot of students who sign up to do research think that they’re going to do a ‘fake’ project.

“When I explain that ‘There is an actual community in Guatemala that has a health problem, and we get to help them figure out what’s going on,’ the students are always pleasantly surprised to learn that they are going to be assisting real people,” says Jacobsen.

“Seeing that moment of connection is something I really treasure,” Jacobsen says. “The joy in my job comes from helping students to develop the knowledge and skills that will allow them to go out and change the world.”

This article appeared in a slightly different form in Dimensions 2010 magazine.

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