Study raises red alert on spread of untreatable malaria with choice drug
There is a red alert that malaria is becoming untreatable with the drug of choice, Artemisinin Combination Therapy (ACT), and the vector, mosquitoes, is becoming resistant to the recommended insecticide, pyrethroids, in more parts of the world.
According to a study published yesterday in the journal, The Lancet Infectious Diseases, a lineage of multidrug resistant Plasmodium falciparum malaria parasites (superbugs), has widely spread and is now established in parts of Thailand, Laos and Cambodia, causing high treatment failure rates for the main falciparum malaria medicines, ACTs.
Also, United Kingdom (UK) doctors reported last week Thursday that a key malaria treatment has failed for the first time in patients being treated in the region.
The clinical reports detailed in the journal Antimicrobial Agents and Chemotherapy showed the therapy failed in four patients between October 2015 and February 2016. The drug combination was unable to cure four patients, who had all visited Africa, in early signs the parasite is evolving resistance.
A team at the London School of Hygiene and Tropical Medicine said it was too early to panic. But it warned things could suddenly get worse and demanded an urgent appraisal of drug-resistance levels in Africa.
However, according to the report, most of the patients were treated with the combination drug: artemether-lumefantrine.In Nigeria, although there are reported cases of treatment failures with ACTs, the National Malaria Elimination Programme (NMEP) insisted that the country has not confirmed any case of malaria resistant to the drug-of-choice, ACTs.
According to The Lancet Infectious Diseases, the emergence and spread of artemisinin drug resistant Plasmodium falciparum lineage represents a serious threat to global malaria control and eradication efforts.
The authors warned that malaria parasites resistant to both artemisinin and its widely used partner drug, Piperaquine, are now spreading quickly throughout Cambodia, with fitter multidrug resistant parasites spreading throughout western Cambodia, southern Laos and northeastern Thailand.
Worried that the further spread of these multidrug resistant parasites through India to sub-Saharan Africa would be a global public health disaster, the study authors called for accelerated efforts in the Greater Mekong Sub-region and closer collaboration to monitor any further spread in neighbouring regions.
Also, a genetic analysis of mosquito populations in Africa showed that recent successes in controlling malaria through treated bednets has led to widespread insecticide resistance in mosquitoes.
According to a study led by Charles Wondji of the Liverpool School of Tropical Medicine, with Kayla Barnes, Gareth Weedall and colleagues in the journal, PLOS Genetics, “Resistance to insecticides in malaria vectors threatens the success of insecticide-based interventions (example insecticide-treated bednets). Unless resistance is managed, recent enormous gains in malaria transmission reduction from scaling up these interventions could be lost.
By elucidating patterns of evolution of insecticide resistance in a major African malaria vector following insecticide-based interventions and generating crucial information to predict the speed and direction of the spread of resistance, this study has shed light on how mosquitoes evolutionarily respond to the massive selection pressure from insecticide-based control interventions across Africa, and provided vital information to help improve the implementation of successful control strategies. This study highlights the risk that if this level of selection and spread of resistance continues unabated, our ability to control malaria with current interventions will be compromised.”
Head of Infection and Immunobiology at Wellcome Trust, Dr. Mike Turner, concurred: “Already hundreds of thousands of people every year die from drug resistant infections, including malaria. If nothing is done, this will increase to millions of people every year by 2050. The Oxford and Mahidol-led results show a worrying spread of malaria parasite resistance. Data to help track resistance to drugs, such as this study, are vital for improving treatment, diagnosis and prevention of drug resistant infections.”