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Drug-resistant malaria may have spread to Burma and, worse, might now be impervious to current first-line drug defenses. Less than a year into the battle to contain resistance, everything that could go wrong may have.In Southeast Asia, malaria has overrun--twice--the pharmaceutical defenses erected against it, evolving resistance to previously potent anti-malarial drugs and ultimately rendering them useless worldwide. Last year, portents of a third such performance appeared. In cases along the Thai-Cambodia border, the first-line drug artemisinin began taking longer to completely clear malaria parasites, suggesting that today's champion had lost a step against a strengthening disease. (See Once again, it's 'Apocalypse Now' in Southeast Asia.)Plans quickly developed to crush this new threat before it spread globally--again. Efforts to eradicate malaria from the affected areas of Cambodia have markedly reduced prevalence of the disease. But preliminary reports now suggest that parasites in some regions of Burma and Vietnam may also respond poorly to artemisin, meaning the original lines of containment might already be breached. In the past, drug-defeating strains originated in Southeast Asia and then spread by human carriers to Africa. Worryingly, researchers are currently working to determine whether artemisinin-resistant malaria has arrived in other parts of the world and if there is a connection to Southeast Asia.
On top of news of a faster-than-expected spread, some evidence suggests that artemisinin is getting slower and slower in some cases. If the trend continues, eventually treatment failure will result, meaning complete resistance to artemisinin when there are no new drugs to take its place.
On the other fronts of the war on malaria, a vaccine candidate, called RTS,S, has moved into final clinical trials. However, the protective effects of the vaccine have varied widely, from 40% to 60%, creating a difficult decision on whether to undertake large and costly vaccination campaigns when RTS,S emerges from clinical trials in 2014. The bright spots at present are insecticide-treated bednets. The bednet campaign has raised awareness, money and most importantly actual usage of the nets in malarial regions of the world.
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