Unprecedented 5×5 square kilometer map of sub-Saharan Africa shows malaria deaths dropping amidst concentrated efforts
The most detailed map ever created showing the scourge of deaths from malaria was released today as a part of a new scientific analysis of the mosquito-borne disease.
The map, which outlines sub-Saharan Africa in a 5-by-5 kilometer grid, was included in a research paper published online in the New England Journal of Medicine. The paper finds a continent-wide decline in malaria death rates over the past 25 years, a steep 57% drop that followed a period of stagnation in West Africa and an escalation in Central Africa.
Countries with the highest death rates in 2000 also saw the sharpest drops in malaria mortality over the past 15 years, such as in Burkina Faso where the rate plummeted nearly 50% from 33.9 deaths per 10,000 to 17.6 in 2015. Nigeria, the country with the heaviest malaria burden, reduced its rate from 23.6 deaths per 10,000 to 10.5 in that same period.
“For health care providers to effectively and efficiently plan and carry out malaria control programs, the spread of the disease must be tracked carefully over time, place, and age,” explained the paper’s lead author Dr. Simon Hay, Director of Geospatial Science at the Institute for Health Metrics and Evaluation (IHME) at the University of Washington. “These declines in deaths confirm the enormous effect of recent efforts and will help inform future initiatives.”
The study also found that the malaria burden can vary within different parts of a country. Nigeria’s densely-populated southern region had the most malaria deaths, while the nation’s rural areas in the north saw the highest rates of death. The researchers also mapped coverage of medications and insecticide-treated bed nets in comparison to areas with high and low death rates.
The total number of fatalities from malaria in Africa reached its peak in 2003, with more than one million malaria-attributed deaths. In 2015, that number dropped to approximately 625,000, despite increases in population.
Two nations, Nigeria and the Democratic Republic of the Congo, had the greatest percentages of malaria-related deaths in 2015, at 31% and 12%, respectively.
“We’ve seen enormous success against malaria in recent years, but continuing that progress will rely on being smarter about how and where we use resources,” said Dr. Peter Gething, Associate Professor at the University of Oxford’s Big Data Institute (BDI) and lead author. “This study shows not just where malaria is killing most people, but how that compares to where the control efforts are currently focused and where we see the biggest opportunities to target bed nets, drugs, and other control measures.”
Based on the Global Burden of Diseases, Injuries, and Risk Factors (GBD) study and the Malaria Atlas Project, research teams from IHME and BDI examined malaria deaths between 1990 and 2015. Children under age 5 were the most vulnerable and had the highest rates and numbers of mortality, comprising more than 73% of all malaria-related deaths. However, this percentage is down from more than 78% in 2000. The share of deaths in people age 15 and older grew from 15% to 21% during the same time period.
“The use of geographically detailed mapping by age to inform malaria control and treatment strategies will become increasingly important as the burden of the disease shifts from children to adults,” Dr. Hay said. “Hundreds of thousands of lives could be saved by scaling-up programs and customizing strategies to address the needs of specific communities.”