DISCON

Recent global history is marked by several instances of civil conflict, where people of the same nationality have taken up arms against each other. The role of the disease environment in outbreaks of civil war has so far been largely overlooked, says Professor Uwe Sunde of the DISCON project, an EU-backed initiative taking a fresh look at the topic

The last fifty years have been marked by regular outbreaks of civil violence across the world, where citizens of the same nation have taken up arms against each other. While issues like ethnic tensions, resource allocation and political representation have often been major factors behind these outbreaks, the role of the disease environment has been largely overlooked, now researchers in the DISCON project are taking a fresh look at the subject. “The basic idea of the project is to bring health into the picture, and find out whether variation in health threats, or the outbreak of epidemics, can have a causal effect on the outbreak of civil violence,” says Professor Uwe Sunde, the project’s Principal Investigator. In some cases external actors have become involved in civil violence, yet Professor Sunde says the project is focused on civil conflict between people of the same nation. “We have different data sources. We’re most interested in intra-state conflicts that are fought among sections of the same nation without external interventions,” he outlines.

There have been many examples of such conflicts over the last fifty years, and Professor Sunde and his colleagues have access to a wealth of data from across the globe in their research. This is combined with further epidemiological information to help researchers build a deeper picture of the role of disease in civil violence. “We use data sources that collect data on conflicts worldwide at a high level of temporal resolution on an annual basis. We combine that with information from epidemiological databases, that measure

disease exposure in terms of infections and diagnosis of certain disease conditions,” says Professor Sunde. Typically a wide range of factors are involved in outbreaks of civil violence, so Professor Sunde aims to exclude other causes aside from the disease environment. “We control for as much we can, including factors like income and ethnic polarisation,” he stresses. “Essentially all measures of potential determinants of civil conflict highlighted in previous research are accounted for in our empirical framework.”

A key step in the project is to establish whether there is a potential causal effect of disease exposure on outbreaks of civil conflict. Professor Sunde and his colleagues have been working on a research paper in this area. “We look at civil war as an outcome, and we use an identification strategy based on exposure

to particular diseases that are essentially non-eradicable, non-preventable, and that cannot be communicated or spread through conflict,” he explains. These diseases are called multi-host vector transmitted diseases (MHVD), examples of which include dengue fever and malaria. “These diseases cannot be transmitted human-to-human – a vector is required. The vector in the case of malaria is a mosquito,” continues Professor Sunde. “This means that in areas where the disease isn’t present, or that aren’t

suitable for that vector, you’re not going to transmit the disease just because troops are coming in. Then you can exploit variations in weather conditions that may or may not suit the vector, to look at variations in exposure to disease.”

This approach allows researchers to look at the causal relationship between disease exposure and outbreaks of civil conflict within a country, rather than the other way round. In a first step, the researchers are investigating variation in time-invariant conditions that affect the population of these vectors. In a second step, they look at the relationship between climatological shocks and the disease environment, exploiting variation within a country over time. “We essentially look at unusual events like heatwaves, droughts, and periods where the temperature was substantially above the mean for a particular area, and then look whether they have a different impact in terms of the outbreak of civil conflict if they happen in an area with few diseases or many diseases.” outlines Professor Sunde. Certain areas are known to have a high exposure to disease, in large part due to geography and climate, while in others exposure is more irregular, another topic of interest to Professor Sunde. “We can look at areas where many MHVDs are endemic and compare them to areas with few MHVDs and look at the effects of particular weather conditions that don’t happen every year,” he says. “In areas with many MHVDs, suitable weather conditions for vectors lead to more violence than in areas with few endemic diseases.”

In a next step, the project investigates the hypothesis that people in areas regularly exposed to a mosquito-borne disease tend to develop a level of immunity after they were first bitten, so that subsequent infections have much more moderate effects. Weather fluctuations that affect disease exposure year-by-year or month-by-month might therefore be an important aspect to consider. “Certain weather conditions in terms of temperature and precipitation clearly influence the development of disease vectors.” explains Professor Sunde.

A prime objective in this research is to heighten awareness of the importance of disease as a factor in outbreaks of civil conflict. While this area of research has been relatively unexplored until now, Professor Sunde and his colleagues have reached some clear findings. “We have found that high exposure to these MHVDs, both in terms of the presence of a lot of pathogens and in interaction with particularly suitable weather conditions, actually leads to an increase in the probability of an outbreak of civil conflict,” he says. The next step in research will be to analyse much more fine-grained data sets, and then take a closer look at public health policies. “We can look at whether health policies have an impact in reducing conflict – the first indications suggest that might be the case,” says Professor Sunde. “We also plan to look again at issues around global warming, which are extremely interesting in that context, because global warming is expanding the habitat for these vectors. Asian Tiger mosquitoes have recently been found in Germany, and southern England.”

Disease Environment and Civil Conflict (DISCON)

The goal of this research project is to investigate the role of the disease environment as a new, so far largely overlooked, determinant of civil conflict, using data at the national and subnational level.

European Commission, Marie SklodowskaCurie Career-Integration Grant, FP7-MCCIG 618641 DISCON

Project Partners • Matteo Cervellati • Simona Valmori

Project Coordinator, Professor Uwe Sunde Ludwig-Maximilians-Universität Seminar für Bevölkerungsökonomie Schackstr. 4/IV Stock, Raum 413 D-80539 München T: +49 (0)89 2180 1280 E: Uwe.sunde@econ.lmu.de W: http://www.popecon.econ.unimuenchen.de/personen/professoren/ sunde/index.html

Cervellati, M., Sunde, U. and Valmori, S. (2016), Pathogens, Weather Shocks, and Civil Conflicts. Economic Journal, forthcoming, doi:10.1111/ecoj.12430

Professor Uwe Sunde

Professor Uwe Sunde holds a chair in population economics at LMU Munich. His research interests include long-term economic development, population economics, and political economy. He obtained his PhD from the University of Bonn and was director of the Swiss Institute for Empirical Economic Research at the University of St.Gallen prior to his current position.