Malaria experts bid to stamp out disease before parasite becomes drug resistant
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Version 0 of 1. Some of the world's leading malaria experts are advocating a radical plan to try to stamp out the disease before resistance to the newest and best drugs used to treat it grows too widespread. Malaria parasites resistant to the artemisinin drugs, which have been key to strategies for controlling the disease, are now common in the key border regions of south-east Asia and are likely to move into India, according to a study. If they reach Africa, as they inevitably will, it is feared the death toll from the disease will soar. Professor Nicholas White, one of the world's foremost malaria experts, is leading calls for a last ditch attempt to use the drugs to eliminate the disease in the worst-affected regions of the world. He is advocating the nuclear option – dosing everyone in malarial endemic regions, whether sick or well, in a bid to stamp out the malaria parasite before the drugs become useless. "It is undeniably a huge challenge – malaria is worst in remote rural areas, where people are most difficult to reach and treat, and it has had a chequered history – which may be why health authorities have yet to accept it," says White in a comment piece for the Guardian website. "But it might just be possible, and it might work, and so growing numbers of experts, myself included, believe we should try it. However difficult, it is our last hope for artemisinin. Unfortunately the window of opportunity is closing fast as resistance spreads and potentially worsens." The spread of resistance threatens all progress made against the disease, and particularly affects babies and pregnant women. Although deaths have come down, thanks mostly to the artemisinin drugs and the use of insecticide impregnated mosquito nets, more than 600,000 people still die of malaria every year – most of them children under five. White, of the Wellcome Trust-funded Mahidol Oxford Tropical Medicine Research Unit (MORU) in Thailand, a collaboration with Oxford University, is senior author of a study published in the New England Journal of Medicine which has traced the spread of resistance. The paper shows resistance to artemisinins among the malaria parasites, which are transmitted by infected mosquitoes, has followed the same pattern as it did with previous anti-malarial drugs. From the Cambodia/Thailand border it has spread and become firmly established in western Cambodia, Thailand, Vietnam, eastern Burma and Northern Cambodia. There are also signs of emerging resistance in central Burma, southern Laos and north-eastern Cambodia. As yet, there is no sign of resistance in the three African sites included in the blood sampling study, in Kenya, Nigeria and Democratic Republic of the Congo. Dr Jeremy Farrar, Director of the Wellcome Trust, testified to the seriousness of the situation. "If resistance spreads out of Asia and into Africa much of the great progress in reducing deaths from malaria will be reversed," he said. "Our ability to respond to these rapidly emerging health problems depends on swift gathering of evidence, which can be quickly translated into public health and clinical interventions that are then implemented. Antimicrobial resistance is happening now. This is not just a threat for the future, it is today's reality." Even in south-east Asia, the drugs are still curing people, because they are given as part of a cocktail with older antimalarials which have some residual power. But as resistance grows, they will increasingly fail. "Frontline ACTs [artemisinin combination therapies] are still very effective at curing the majority of patients. But we need to be vigilant as cure rates have fallen in areas where artemisinin resistance is established," said Dr Elizabeth Ashley, lead scientist on the study and clinical researcher at MORU. "Action is needed to prevent the spread of resistance from Myanmar [Burma] into neighbouring Bangladesh and India. The artemisinin drugs are arguably the best antimalarials we have ever had. We need to conserve them in areas where they are still working well." |