In a disturbing development, a newly-mutated strain of drug-resistant malaria has spread into Vietnam, complicating efforts to contain the the mosquito-borne virus in Southeast Asia and potentially posing a global threat.
"A single mutant strain of very drug resistant malaria has now spread from western Cambodia to north-eastern Thailand, southern Laos and into southern Vietnam and caused a large increase in treatment failure of patients with malaria", says letter co-author Oxford Prof.
The strain emerged a few years ago in Cambodia, and has since spread to Thailand and Laos.
"It spread like a wildfire to Vietnam", professor Arjen Dondorp, head of malaria department at the tropical medicine research unit at Mahidol University in Bangkok, told AFP. This so-called "superbug" can not be treated with first-line anti-malarial drugs.
Vietnam's Ministry of Health had said in April that malaria resistant to artemisinin has been reported in five provinces and was threatening to spread nationwide.
There have now been "alarming rates of failure", the letter said. The fast spread of the mutated strain of the unsafe disease is an alarming global threat, scientists have warned. The World Health Organisation claims that 1.5 million people are infected with malaria in southeast Asia annually, resulting in over 600 deaths.
The first choice treatment for malaria is artemisinin in combination with piperaquine.
The World Health Organization reports there has been recent, dramatic progress with the significant reduction of the number of people being diagnosed with malaria, with a 21 percent decrease in incidence from 2010 to 2015 and a 29 percent drop in mortality during that time. It's the continent from which malaria emerged, and where Anopheles mosquitoes, the insect responsible for spreading the disease, are plentiful.
Resistance to the drugs would be catastrophic in Africa, where 92 per cent of all malaria cases happen.