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Wiping out malaria in much of sub-Saharan Africa is an attainable goal that can be reached with targeted and consistent intervention, according to research published today (Mar. 12) in PLoS ONE. (UPDATE: A link to the study has been added.)

Scientists mathematically modeling the spread of malaria in eight African regions have, for the first time, identified threshold levels of malaria transmission. If malaria control efforts keep transmission rates below these thresholds, their model predicts, sustainable management or eradication of the disease is possible.

"This is an exciting possibility," London School of Hygiene and Tropical Medicine parasitologist Colin Sutherland, who was not involved in the research, told The Scientist. "Malaria does appear to be quite eraticatable, if I can use a terrible word."

Gabriela Gomes, a theoretical epidemiologist at the Instituto Gulbenkian de Ciencia in Portugal who led the research team, says that her model can give public health administrators distinct goals for reducing malaria transmission rates. "[This research] could help to define practical targets," Gomes told The Scientist, "but before we get there we have to get more data." She said that she hopes to improve upon her model by testing it with more data from malaria-stricken regions - such as individual infection levels from cohort studies.

Gomes and her colleagues are also the first to estimate the importance of transmission from asymptomatic parasite carriers, whose continued exposure to malaria dampens their clinical response, but makes them a reservoir for transmission. "[Gomes] and her colleagues have understood that the way we've thought about the reproductive rate [of malaria parasites]," said Sutherland, "ignores the fact that there are a lot of people who have had malaria before that still transmit the disease."

Gomes said that public health managers could use her malaria model, and others like it, to address the disconnect between administration and assessment of global health interventions, which I wrote about in our March issue. For example, the threshold transmission levels her model predicts could be used as a marker to monitor the impact of malaria interventions, such as drug or bed net distribution, she said. Sutherland agreed. "I would advocate longer-term planning that aims to continue improving interventions to drive transmission rates down."