Malaria Hotspots Worldwide May Benefit from 1930s Style Public Health Interventions

A new study suggests that malaria was eliminated from the US South in the 1930s not by people moving away from mosquito breeding grounds, but rather because of targeted public health interventions and the development of local public health infrastructure.

Researchers behind the study suggests that the same public health moves could be made in parts of the world where malaria is still present.

"We found that targeted public health interventions, supported by the federally backed development of state and local public health infrastructure, led to the decline of malaria despite widespread and deep-seated poverty" in the American South, said Daniel Sledge, assistant professor of political science at University of Texas, Arlington and lead author of the new study, which is published in the American Journal of Public Health.

Infected mosquitoes transmit malaria. People infected with malaria suffer from fever, headache and vomiting. If left untreated, malaria can be deadly. In 2010, malaria killed 1.24 million people worldwide, the researchers report, adding that the disease causes widespread economic downfalls as well.

In the American South, malaria was similarly devastating as workers' productivity was undermined by the disease and people from other areas were reluctant to migrate to the region, which hurt the region economically until the disease was eradicated in the late 1930s.

Sledge and his colleagues sought to assess the economic impacts malaria has on the American South in during the first part of the 20th century. They analyzed the decline of malaria in each of the 67 counties in Alabama -- an archetypal Deep South state that experienced high levels of malaria well into the 1930s.

"In the model, we categorized counties into three risk levels and then estimated the dependence of mortality rates on variables related to weather, [federal Works Progress Administration] projects and population movement," said co-author George Mohler, assistant professor of mathematics and computer science at Santa Clara University in California. "After drought, the most important variable for predicting a decline in mortality rates was the amount of drainage in a county, rather than movement out of high risk counties or a reduction in tenant farms."

The researchers point to the importance of drainage work, screening and public health infrastructure as well as the training of public health workers in the elimination of the disease.

Sledge and Mohler contend that similar practices in malaria-stricken locations around the world may have similar positive results, they argue that malaria can be controlled in the face of poverty and economic dislocation without major social change.

"Today, disease surveillance, drainage measures and screening work to ensure that, on those occasions when malaria is reintroduced from outside of the U.S., the chain of transmission does not begin again," Sledge said.