Scientists release new map of global malaria risk

WASHINGTON, Feb. 27 (Xinhua) -- Researchers have released a detailed map of global malaria risk, showing that some at-risk countries are getting less investment per capita than others, according to the latest issue of online journal PLoS Medicine.

An international team of researchers compiled data on malaria incidence reported by countries and research groups from 2002 through 2006, and climate data such as temperature and aridity that limit malaria transmission.

The new map illustrates that 2.37 billion people -- 35 percent of the world's population -- have some risk of acquiring malaria.

The finding diminishes previous risk estimates of 46 percent and 48 percent published respectively in 1994 and 2002.

There are 1 billion people living in high-risk areas with the infection rates outside Africa put at less than 5 percent.

Malaria, a mosquito-borne disease caused by the parasite Plasmodium falciparum, infects some 500 million people each year and kills 1 million of them.

Sub-Saharan Africa is by far the most severely affected area, but comprehensive data on a global scale are lacking. The most recent world map of malaria was created in 1968, while funding agencies are left guessing where the money is needed most.

In 2006, the Wellcome Trust in the United Kingdom and institutions based around the world launched the Malaria Atlas Project to map, model and predict global malaria risk.

Their new map highlights some disparities between risk and funding, says epidemiologist Carlos Guerra of the University of Oxford, UK, who led the study.

For example, the at-risk populations in Southeast Asia and Africa receive less funding per capita than people living in lower risk regions such as the South American country of Suriname.

Guerra applauds rapid progress in South America but says the current per capita funds are simply not enough to meet eradication goals, arguing that money needs to be re-allocated to areas where malaria is "a huge problem."

About 1 billion U.S. dollars a year goes into malaria treatment and prevention, though people do not know whether the money is hitting the best targets. So public health experts hope the new information will help them realign their malaria-eradication efforts to better meet the threat.

The mapping results are unprecedented in their precision, says malaria biologist Dyann Wirth of the Harvard School of Public Health in Boston, who was not involved in the project. The work signals a "maturation" in the field of malaria research and provides an important baseline in determining the success of future malaria interventions, she says.