Use of artemisia annua L. infusion for malaria prevention: mode of action and benefits in a Ugandan community

Abstract

Malaria is major public health problem in Uganda endemic in 95% contributing up to 40% of hospital outpatient attendances. Approaches to controlling the disease include; environmental, entomological and medicinal interventions. Some communities use medicinal plants to control the disease. In this paper we report the use of Artemisia annua L. for malaria prophylaxis at a Ugandan floricultural farm. We conducted a survey of the farm workers to determine extent of use of A. annua ‘tea’, their clinic attendance patterns and also quantified the levels of artemisinin and flavonoids in A. annua. We further tested the effect of artemisinin devoid extract in laboratory animal models. Findings from the survey showed that 84.2% of the managers and 62% of field workers in this farm consumed A. annua ‘tea’ once a week to prevent malaria and related fevers. Clinic attendance due to fevers or symptoms associated with malaria was reduced by 80% while cases of laboratory confirmed diagnosis of malaria reduced by 16.7%. Laboratory test of A. annua leaf powder used in community indicated the presence of artemisinin (0.4% to 0.5%) and flavonoids (9% to 11%). A. annua extract devoid of artemisinin was found to significantly boost monocyte counts in albino rats (p<0.001).The action of these flovonoids could explain the mechanism of prophylaxis of A. annua ‘tea’. A. annua variety or product thereof rich in flavonoids but devoid of artemisinin should be developed and tried for mass prevention of malaria as a beverage or food taken regularly.