Image by Ute Frevert
and Margaret Shear
New research provides genetic evidence that malaria parasites in Africa are developing resistance to antimalarial drugs.
Researchers found that Plasmodium falciparum parasites with a mutation in the gene ap2mu were less sensitive to both artemisinin and quinine.
A study published in 2013 suggested a link between a mutation in ap2mu and low levels of malaria parasites remaining in the blood of Kenyan children after treatment with artemisinin.
However, further research was needed to confirm that these genetic characteristics represented an early step toward resistance.
In the new study, published in Antimicrobial Agents and Chemotherapy, researchers genetically altered the malaria parasite to mutate ap2mu in the same way that had been observed in Kenya.
The team found the altered parasite was significantly less susceptible to treatment, requiring 32% more drug to be killed by artemisinin. The genetically altered parasite was also 42.4% less susceptible to quinine.
Earlier this year, a different research group discovered mutations in the gene kelch13, which were linked to reduced susceptibility to artemisinin combination treatment in South East Asia.
Historically, resistance to antimalarial medicines has emerged in South East Asia and then spread to Africa. But these new findings suggest a different route to drug resistance may be developing independently in Africa.
“Our findings could be a sign of much worse things to come for malaria in Africa,” said study author Colin Sutherland, PhD, of the London School of Hygiene & Tropical Medicine in the UK.
“The malaria parasite is constantly evolving to evade our control efforts. We’ve already moved away from using quinine to treat cases as the malaria parasite has become more resistant to it, but if further drug resistance were to develop against our most valuable malaria drug, artemisinin, we would be facing a grave situation.”
“We now know that the gene ap2mu is an important factor in determining how well our drugs kill malaria parasites. We will be conducting laboratory and field studies to more accurately measure the impact of mutations in the ap2mu gene. We hope our findings will help [us] understand resistance of malaria to drugs and potentially be an important tool for monitoring malaria treatment in the future.”
