Artemisinin has been a linchpin of malaria treatment in recent years, but if it becomes widely ineffective, there is nothing quite ready in the reserves to take its place. "I think the best way to beat microbial resistance is to identify new drug targets," Sullivan says. But, as Anne-Catrin Uhlemann and David Fidock in an essay in the same issue of The Lancet wrote, "drug development efforts are not expected to yield new antimalarials until the end of this decade."
Other drugs in the combination-treatment pyramid have already balked. As Anderson notes, many of the parasites in Thailand were already resistant to another antimalarial, mefloquine, "so the situation was held in the balance by artemisinin."
A malaria vaccine, made by GlaxoSmithKline, is in clinical trials, and a 2011 paper reported promising results, showing that it seemed to protect about half of the kids who received it. But Anderson is not holding his breath and hoping that the vaccine arrives before artemisinin resistance picks up any more speed. "We've been treading water for the past 25 years waiting for the vaccine," he says.
"Drug treatment is still the mainstay of malaria control, and we really don't have another drug to fall back on," Anderson says.