People living in the vicinity of dams in Africa will likely see a doubling of the odds they will get malaria because of climate change. Some 25 million people will be at increased risk by 2080, according to a new study published in Malaria Journal. The construction of dams across Africa has helped improve food security and spur development, but they may pose a public health problem.
“While dams clearly bring many benefits, the present study confirmed that the role of climate change on malaria around dams will fundamentally alter the current impact of dams on malaria,” said biologist Solomon Kibret of the University of California, the paper’s lead author, in a statement. “Given the impending magnification in the threat of mosquito-borne infections, there is urgent need for proactive measures that mitigate the health risks of today and tomorrow.”
Currently 1 million cases of malaria occur each year in the vicinity of 1,268 dams located in sub-Saharan Africa. Climate change will make malaria seasons longer, increasing the number of cases. Prior research estimates that in highland parts of Africa every 1 degree Celsius increase in average temperature will result in 3 million more malaria cases.
By modeling climate change predictions, the researchers determined that the total area supporting the transmission of malaria will increase. Large pools of water held by dams make for the ideal mosquito breeding ground. The resulting combination means that the number of cases near dams could spike to about 3 million a year by the 2080s, triple that of today.
Most concerning is that this could lead to the return of malaria to regions currently free from the parasite. The lack of preparedness could be “disastrous” for those communities, according to the report’s authors. Malaria control efforts will have to take into consideration the potential changes in order to maintain momentum towards elimination.
It means doing more than what is happening already. Research from last year showed that bed nets, insecticides and other conventional measures to control malaria were not very effective in dam areas. Countries may have to consider drying out dam waters or altering designs of proposed projects in order to keep away mosquitoes.
“The time for putting on the table currently sidelined measures for malaria control around reservoirs, such as water-level management, is long overdue,” said Jonathan Lautze, senior researcher at IWMI-southern Africa and report co-author, in a statement.
Malaria kills about 400,000 people per year in sub-Saharan Africa. It is home to 88 percent of the world’s cases and 90 percent of deaths. Children are disproportionately affected by the parasite, accounting for more than two-thirds of all deaths. It raises the urgency to build on the nearly 6 million lives saved since 2000.