Drug-resistant malaria is spreading in South East Asia, and has now reached the Cambodia-Thailand border, according to a study.
“Radical action” is needed to prevent further spread of malaria parasites resistant to key drugs, say scientists.
The spread could undermine recent gains in malaria control, they report in the New England Journal of Medicine.
No evidence was found of resistance in three African sites — Kenya, Nigeria and the Democratic Republic of Congo.
The study analysed blood samples from more than 1,000 malaria patients in 10 countries across Asia and Africa.
It found the malaria parasite had developed resistance to front-line drugs known as artemisinins, in western and northern Cambodia, Thailand, Vietnam, and eastern Burma, also known as Myanmar.
There were signs of emerging resistance in central Burma, southern Laos and north-eastern Cambodia.
Of particular concern was the corner of Asia on the Cambodia-Thailand border, where resistance to other anti-malarial drugs has emerged in the past.
“Resistance is now present over much of South East Asia,” said lead scientist Prof Nicholas White, of the University of Oxford.
“It’s worse than we expected.
“We have to act quickly if we are going to do anything.”
Prof White said it might be possible to prevent further spread, but conventional malaria-control approaches would not be enough.
