Hunger in Zimbabwe set off TB outbreak

"Political instability can lead to economic instability, and this can lead to a health crisis with the most vulnerable people in society the most likely to be harmed,” says Michael Silverman. (Credit: DFAT Photo Library/Flickr)

New research links the rise of tuberculosis in Zimbabwe during the political and economic crisis of 2008-2009 to widespread food shortage.

Between 2000 and 2007, Zimbabwe underwent an economic collapse characterized by political crises, hyperinflation, and a real GDP reduction of 40 percent. After a controversial election, GDP fell an additional 14 percent in 2008.


The researchers wanted to determine whether the widespread food shortage would weaken the immune systems of the population and lead to a rise in tuberculosis incidence.

Researchers assessed the incidence of TB at two mission hospitals that remained open during the crisis. Although geographically far apart, both hospitals demonstrated a rise in the number of TB cases as the hunger associated with the crisis worsened.

“This was the first study to detect the recent TB outbreak in Zimbabwe, and the first anywhere to suggest an association between rising TB incidence and national economic decline in the absence of armed conflict,” says Michael Silverman, assistant professor at the Dalla Lana School of Public Health at the University of Toronto and senior author of the study, which appears in PLOS ONE.

HIV’s role in the outbreak

Although the same phenomenon may occur with other infectious diseases, the study focused on TB, which is one of the largest causes of morbidity and mortality in Zimbabwe, especially among people living with HIV.

“Zimbabwe may have been predisposed to this TB outbreak due to the presence of a large HIV-positive population who were particularly vulnerable to the effects of food shortages which led to malnutrition and further damage to already weakened immune systems,” says Silverman.

Many developing countries have large HIV-positive populations and thus socioeconomic instability could lead to a similar rise in tuberculosis rates elsewhere.

“This finding emphasizes the importance of adequate food availability in controlling TB incidence, particularly in areas with high HIV prevalence,” Silverman says.

The study also demonstrated that TB incidence appears to be seasonal, with a larger number of cases when food is scarce in the dry season and lower numbers of cases post-harvest when food is more plentiful. Research data also suggests that TB incidence fell back to pre-crisis levels when the economy of the country and food security improved after 2009.

“Political instability can lead to economic instability, and this can lead to a health crisis with the most vulnerable people in society the most likely to be harmed,” says Silverman.

“It is important for political leaders to be aware that in addition to economic costs, political conflict can potentially have very serious health implications for vulnerable communities.”

Additional researchers from the University of Ottoawa, University of Toronto, University of Zimbabwe, Howard Hospital in Zimbabwe, Brigham and Women’s Hospital and Children’s Hospital of Boston,the Murabinda Mission Hospital in Zimbabwe, and King’s College Hospital in the UK contributed to the research.

Source: University of Toronto