The most detailed map ever created of malaria risk worldwide is published today by an international team of researchers funded by the Wellcome Trust. The Malaria Atlas Project (MAP) will be a powerful tool for helping target malaria control programmes and suggests that elimination of malaria in three-quarters of the world's at-risk areas might be less difficult than previously thought.
Details of the map are published in the open access journal PLoS Medicine and are available online at www.map.ox.ac.uk. It represents the culmination of two years' research with contributions from over two hundred scientists and malaria control experts, led by the Kenya Medical Research Institute (KEMRI)-Wellcome Trust programme and the University of Oxford. The researchers used state of the art mathematical modelling, spatial analyses and supercomputing technology to develop a map which pinpoints malaria risk to an unprecedented resolution of 25km2.
Malaria is a potentially deadly disease which kills over a million people each year, mainly young children and pregnant women. It is caused by malaria parasites, which are injected into the bloodstream by infected mosquitoes. There are a number of species of the parasite, but the initial focus of the MAP has been on the most deadly form, Plasmodium falciparum, which is responsible for nine out of ten deaths from malaria.
The project shows that 2.4 billion people are at risk from the most deadly form of malaria, but highlights some promising news: three-quarters live in areas where risk is considered very low and the technical obstacles to malaria control are relatively small. However, the map shows that almost all of those living in areas of high transmission live in sub-Saharan Africa where the disease, death and disability burdens from P. falciparum malaria remain high.
"This map of malaria risk gives us hope that eliminating malaria in many countries is technically feasible," says Dr Simon Hay, who manages the project from the University of Oxford. "But it also presents us with a blunt truth – that the burden facing the people of Africa is very high and that tackling malaria there will remain a great and long term challenge."
In the 2008 Global Malaria Action Plan, the Roll Back Malaria partnership of the World Health Organization set ambitious targets for increases in intervention coverage and the impacts that these should have on the global toll of malaria cases and deaths. They also committed to elimination of the disease in countries where this was feasible and re-tabled the long term goal of malaria eradication.
"Mapping malaria has never been more important," says Dr Hay. "The map published today will be updated annually and will enable us to monitor and evaluate progress towards international targets for control and elimination."
Dr Hay and colleagues have compiled information based on medical intelligence, satellite-derived climate data and the largest ever archive of over 11,000 community-based estimates of parasite prevalence. These data were assembled and analysed by a team of geographers, statisticians, epidemiologists, biologists and public health specialists.
Professor Bob Snow, who heads the MAP group in Kenya, says: "Charting the future success of the international effort to control and eliminate malaria requires a map of where we are today. Rather than guessing what progress has been made, MAP will record, model and track what's happened, giving donors and national governments an evidence-based perspective on what investment has achieved."
Most of the international support for malaria endemic countries is co-ordinated by the Global Fund for AIDs, TB and Malaria. The MAP has been welcomed by its Executive Director, Professor Michel Kazatchkine:
"We need to increase the information available to us and to our donors to demonstrate that investing in malaria control does indeed reduce the numbers of people at risk worldwide. With this kind of information, we can reassure donors by graphically showing progress and highlight where further investments are most needed."
In accordance with the ethos of the Wellcome Trust, which funded MAP, all data generated will all be placed in the public domain so that it can be used freely by anyone, such as researchers, policy makers and non-governmental organisations (NGOs).
"The Malaria Atlas Project will offer a valuable resource to all those involved in malaria control," says Sir Mark Walport, Director of the Wellcome Trust. "By making its data freely available, we can maximise its usage and impact, and help curb this devastating disease."
Source: Wellcome Trust
Map highlighting levels of P. falciparum endemicity (darker regions relate to higher levels).
(Photo Credit: Malaria Atlas Project)