WASHINGTON, July 30 (Xinhua) -- Drug-resistant malaria is now widespread in Southeast Asia, seriously threatening global efforts to control malaria, a new study warned Wednesday.
An analysis of blood samples from 1,241 malaria patients in 10 countries across Asia and Africa found resistance to the world's most effective anti-malarial drug, artemisinin, is now firmly established in western and northern Cambodia, Thailand, Vietnam and eastern Myanmar.
There are also signs of emerging resistance in central Myanmar, southern Laos and northeastern Cambodia, researchers reported in the U.S. journal New England Journal of Medicine.
Of particular concern is the corner of Asia on the Cambodia- Thailand border, where malaria parasites have developed resistance to two other anti-malarial drugs in the past.
Reassuringly, there are no signs of resistance in the three African sites included in the study, located in Kenya, Nigeria and Democratic Republic of the Congo.
The study said that extending the course of antimalarial treatment in areas with established resistance -- for six days rather than the standard three days -- could offer a temporary solution to this worsening problem.
Actions are also needed to prevent the spread of resistance from Myanmar into neighboring Bangladesh and India, the researchers said.
"It may still be possible to prevent the spread of artemisinin resistant malaria parasites across Asia and then to Africa by eliminating them, but that window of opportunity is closing fast," senior author Nicholas White, professor of tropical medicine at the University of Oxford, said in a statement.
"Conventional malaria control approaches won't be enough -- we will need to take more radical action and make this a global public health priority, without delay," White said.
The study was conducted at 15 trial sites in Southeast Asia and Africa between May 2011 and April 2013.
Currently, there are new anti-malarial medicines in development, but they are unlikely to be available for widespread distribution for several years, the researchers said.
"The artemisinin drugs are arguably the best anti-malarials we have ever had. We need to conserve them in areas where they are still working well," said Elizabeth Ashley of the University of Oxford who led the study.
Although there has been a substantial reduction in the number of people falling ill and dying from malaria, with approximately 3. 3 million deaths prevented since 2000, it is estimated that more than 600,000 people still die from the disease each year, most of them children under five years of age living in Africa.