Bengaluru: Detection of malaria parasites resistant to the frontline artemisinin (ART) combination therapy in some south Asian countries should worry India, Govindarajan Padmanabhan a top biochemist and malaria researcher at the Indian Institute of Science here has warned.
“Africa and India can as well be the superbug’s next destination and, if it spreads, this will pose a disaster,” Padmanabhan told this correspondent, adding: “Sri Lanka is supposed to be malaria-free and it too should start worrying.”
The British journal “Lancet Infectious Diseases” had recently reported that P. falciparum malaria parasites resistant to both ART and its widely used partner drug, piperaquine, are now spreading quickly throughout western Cambodia, southern Laos and northeastern Thailand.
The study, by researchers at Mahidol University in Thailand and Oxford University, warned that “the consequences of resistance spreading further into India and Africa could be grave if drug resistance is not tackled from a global public health emergency perspective”.
Artemisinin, also known as qinghaosu — extracted from the “Artemisia annua” plant — is a powerful and perhaps the only really effective anti-malarial at present. But because ART has a very short half-life, the World Health Organisation had insisted that it should only be used as a combination with another long-acting anti-malarial.
Thus came the combination therapies: ART-lumefantrine, ART-meflaquine, ART- Sulfadoxine/pyrimethamine (ART-SP) and Dihydroartemisinin-piperaquine (DHA-PPQ).
Padmanabhan said that over the years, the malaria parasite had developed resistance even to many combination therapies, except DHA-PPQ, that had remained very effective.
“Now the recent report of the parasite’s resistance to this combination also is really worrisome.”
“The spread of resistance will be a huge challenge to health workers,” he said. “This challenge will always go on and that is why I really want to try ART-curcumin combination, which may be an answer to resistance development,” the scientist noted.
Curcumin, is the compound that gives turmeric (haldi) its trademark bright yellow colour.
The ART-curcumin combination is unique, with potential advantages over the known combination therapies, Padmanabhan said. In trials carried out on mice, three oral doses of curcumin following a single injection of artemisinin to infected mice were able to ensure almost 100 per cent survival of the animals.
In addition to having a direct killing effect as an anti-malarial, curcumin is also able to prime the immune system against malaria parasites in mice “rendering the combination to act like a therapeutic vaccine”, Padmanabhan said.
“Thus, this combination has unique potential to prevent parasite recrudescence and relapse. Besides it is cheap and no resistance against it is known since it is a dietary supplement.”
Padmanaban and his team are hoping to start human trials of an artemisinin-curcumin combination therapy in both simple malaria cases and in the treatment of the deadly cerebral malaria. He said regulatory clearances are awaited.