No place on the map measures up to the Thai-Cambodian border for breeding super strains of malaria. The forest region, a magnet for gem miners searching for pigeon blood rubies and Pailin blue sapphires, has already twice spawned resistance to our best drugs, once in the 60s and again in the late 80s. So maybe Tuesday's news in the New York Times—as dire as it is—should come as no surprise: the borderland bug has developed a defense against the white knight pill in the battle against malaria, artemisinin. The consequences could undermine the $45 billion international campaign to roll back the disease. Even worse, there's potential to spark a mega-epidemic, for which we have no response.
Before you cancel your trip to Asia, there are a few things you ought to know: evidence about the extent of the bug's resistance and its penetration outside the region is murky at best. In The New England Journal of Medicine study cited by the paper, only two out of 60 subjects had artemisinin-resistant malaria. It’s a small number, but dangerous nonetheless, since super microbes will multiply where others cannot (see: Darwinism). An important caveat to note is that patients were treated solely with artemisinin.
All of today's treatments combine artemisinin with another antimalarial (called ACTs). That way, if a single protozoa develops resistance to one drug, it'll still be wiped out by another, and never have the opportunity to spread its genetic code. The chances for one bug to find the mutant mix to overcome two drugs at once are astronomical. Though that doesn't get us out of the woods, it does significantly improve our chances and slows the spread of the new breed.
Worse news comes from field studies in western Cambodia, which report that even combination therapies have been partly compromised, showing them to be effective against 80-90 percent of cases. But even those results are murky; it's unclear whether patients were taking the prescribed dosages or even unadulterated pills (most drugs in the region are sold privately and unregulated). One thing is certain: borderland malaria has become tougher for ACTs to kill than ever before, taking seven days instead of what was once three.
The traveler in East Asia needn’t worry just yet. The borderland strain still only inhabits the western provinces of Thailand. Attractions like the beaches in the south and east, Siem Reap, and Angkor Wat all remain unexposed. If you do plan on a stint with the borderland gem miners, take a prophylactic like atovaquone, (brand name Malarone)—no strain has found a defense against it. Yet.
Illustration by Dan Saelinger