Jennifer Rankin
Is Artemisia annua L. herbal infusion an effective, safe, readily available treatment of uncomplicated malaria in East Africa? - A literature review
Abstract
Artemisia annua L. (annual or sweet wormwood) is an effective antimalarial, of low-toxicity, treating drug-resistant plasmodium malaria. This activity has been attributed to the sesquiterpene lactone, artemisinin, which contains an endoperoxide bridge unique among antimalarial preparations. Pharmacokinetics studies demonstrated artemisinin is rapidly absorbed and maximum concentration levels were achieved 30 minutes after ingestion of the herbal infusion and exceeded the minimum concentration (9ng/ml) necessary to inhibit proliferation of plasmodium falciparum parasites. The short elimination half-life (1-3 hours after oral administration) has been cited as a reason for potential development of malarial parasite-resistance but may actually prevent this by limiting the time malarial parasites are exposed to sub-therapeutic levels.
The clinical endpoints of parasite clearance time (PCT) and fever subsistence time (FST) were achieved more rapidly with the administration of the herbal infusion (5g / L) than with quinoline pharmaceuticals. Unlike other antimalarials artemisinin acts at the early trophozoite stages of the erythrocyte-cycle and exerted a gametocytocidal effect possibly reducing the transmission rates of malaria.
Parasite-clearance requires adequate artemisinin levels over 3-4 parasite life-cycles. Short courses led to high recrudescence rates therefore it is recommended that the herbal infusion is given over 7 days to achieve a 28 day cure.
Methods: -a critical analysis of the literature from the medical and pharmaceutical journals with particular reference to East Africa was conducted. A brief field trip to Kenya and Tanzania was also undertaken to determine how A. annua was utilised on the field.
