By Sanjeet Bagcchi
[NEW DELHI] Medical researchers say that mass administration of combination drugs can stop the transmission of malaria caused by the Plasmodium falciparum parasite and reduce its prevalence in South-East Asian countries, where resistance of the disease to artemisinin, the standard drug, has hampered elimination efforts.
According to WHO, globally, there were 219 million cases of malaria in 2017, which resulted in 435,000 deaths. P. falciparum accounted for 97 per cent of the deaths in Africa, 71.9 per cent for both the Western Pacific and the Eastern Mediterranean, and 62.8 per cent in South-East Asia.
Elimination of malaria in a defined geographical area depends on the interruption of local transmission (reduction to zero incidence of indigenous cases) of a specified malaria parasite species, says WHO.
“This [falciparum] is the most dangerous form of malaria; in the Greater Mekong sub-region, it is becoming resistant to many types of anti-malarial drugs”
Roland Gosling, University of California
Lorenz Von Seidlein, lead researcher at the Mahidol Oxford Tropical Medicine Research Unit, Bangkok, tells SciDev.Net that mass drug administration (MDA) as “presumptive treatment” (to clear the parasite reservoir) was carried out on 8,445 people in eight villages spread across Cambodia, Laos, Myanmar and Vietnam as part of a study. The result was published February in the journal PLoS Medicine.
By the third month of administrating the anti-malaria drugs dihydroartemisinin-piperaquine and low-dose primaquine, the prevalence of P. falciparum had decreased by 92 per cent in villages where MDA had been carried out. Over the subsequent nine months, P. falciparum infections returned but stayed well below baseline levels, the study said.
The emergence and spread of multidrug-resistant P. falciparum in the Greater Mekong sub-region threatens global malaria elimination efforts. MDA, the presumptive antimalarial treatment of an entire population to clear the subclinical parasite reservoir, is a strategy to accelerate malaria elimination,” Seidlein and colleagues said in the journal.
According to Seidlein, using MDA against malaria is not a new strategy and has been around for 100 years. “But it requires the administration of relatively large amounts of antimalarial drugs; [additionally,] considerable resources go into community engagement.”
Roland Gosling who leads the malaria elimination group at the University of California, where he is associate professor of epidemiology and biostatistics, says that the idea of MDA is to be very active against malaria for a short time. “Even if it costs more, it can save money in the future by stopping drug-resistant malaria spreading elsewhere in the world.
“This [falciparum] is the most dangerous form of malaria; in the Greater Mekong sub-region, it is becoming resistant to many types of antimalarial drugs,” Gosling says. “A good investment, in my mind.”
“This [falciparum] is the most dangerous form of malaria; in the Greater Mekong sub-region, it is becoming resistant to many types of anti-malarial drugs,” Gosling says. “A good investment, in my mind.”