Lack of adherence to the full course of Artemisinin-based combination therapy (ACT) treatment is threatening the effectiveness of the drug recommended as first-line treatment for uncomplicated malaria in countries where the disease is endemic, according to recent studies. In Siaya district of western Kenya, where malaria is particularly prevalent (38 per cent incidence in 2010), a study revealed that only 47 per cent of participants reported completing the given doses.