Burma and the Mekong River area of Southeast Asia is the breeding ground.
From The Irrawaddy (emphasis mine):
WASHINGTON — US experts are raising the alarm over the spread of drug-resistant malaria in Burma and several Southeast Asian countries, endangering major global gains in fighting the mosquito-borne disease that kills more than 600,000 people annually.
While the communicable disease wreaks its heaviest toll in Africa, it’s in nations along the Mekong River where the most serious threat to treating it has emerged.
[….]
The report warns that could be a health catastrophe in the making, as no alternative anti-malarial drug is on the horizon. The UN World Health Organization (WHO) is warning that what seems to be a localized threat could easily get out of control and have serious implications for global health.
“Absent elimination of the malaria parasite in the Mekong, it is only a matter of time before artemisinin resistance becomes the global norm, reversing the recent gains,” writes Dr. Christopher Daniel, former commander of the US Naval Medical Research Center, in the report for a conference at the Washington think tank Tuesday.
[….]
Nowhere are the challenges in countering the threat to drug-resistance greater than in Burma. Some 70 percent of its 55 million people live in malaria-endemic areas, and as a nation, it accounts for about three-quarters of malaria infections and deaths in the Mekong region, the report says.
[….]
It’s an issue of regional concern as Burma has large transient populations in its border regions, including ethnic minorities displaced by fighting and migrant workers who cross borders.
There is more, read it all.
The US resettled 16,299 Burmese refugees to your towns and cities in fiscal year 2013 alone (second only to the number of Iraqis which topped 19,000), click here. Were they all tested?
Update: Superbugs could erase a century of medical advances, here.