Therapeutic efficacy of artesunate-amodiaquine and artemether-lumefantrine combinations in the treatment of uncomplicated malaria in two ecological zones in Ghana

BACKGROUND: Case management based on prompt diagnosis and adequate treatment using artemisinin-based combination therapy (ACT) remains the main focus of malaria control in Ghana. As part of routine surveillance on the therapeutic efficacy of ACT in Ghana, the efficacy of amodiaquine-artesunate (AS-AQ) and artemether-lumefantrine (AL) were studied in six sentinel sites representing the forest and savannah zones of the country. METHODS: Three sites representing the two ecological zones studied AS-AQ whilst the other three sites studied AL. In each site, the study was a one-arm prospective evaluation of the clinical, parasitological, and haematological responses to directly observed therapy for uncomplicated malaria with either AS-AQ or AL among children aged 6 months and 9 years. The WHO 2009 protocol for monitoring anti-malarial drug efficacy was used for the study between July 2013 and March 2014. RESULTS: Per-protocol analyses on day 28 showed an overall PCR-corrected cure rate of 100% for AS-AQ and 97.6% (95% CI 93.1, 99.5) for AL: 97.2% (95% CI 92.0, 99.4) in the forest zone and 100% in the savannah zone. Kaplan-Meier survival analysis showed similar outcomes. Prevalence of fever decreased by about 75% after the first day of treatment with each ACT in the two ecological zones. No child studied was parasitaemic on day 3, and gametocytaemia was generally maintained at low levels (<5%). Post-treatment mean haemoglobin concentrations significantly increased in the two ecological zones. CONCLUSIONS: Therapeutic efficacy of AS-AQ and AL remains over 90% in the forest and savannah zones of Ghana. Additionally, post-treatment parasitaemia on day 3 is rare suggesting that artemisinin is still efficacious in Ghana.