Parasite Clearance Time and Time to Recurrent Infection Following Treatment With Artemether/Lumefantrine Among Children With Uncomplicated P. Falciparum Malaria Five Years After Wide Scale Use of the Drug in Tanzania

Artemether/Lumefantrine (AL) has been in wide scale use in Tanzania since 2007 as first line treatment for uncomplicated falciparum malaria. Nonetheless, reports of confirmed resistance against Artemisinin derivatives expressed phenotypically as prolonged parasite clearance have emerged from South-East Asia (SEA), signifying reduced parasites susceptibility to the otherwise rapidly acting artemisinins. Prolonged clearance is associated with an increase in day 28 treatment failure, gametocytes carriage and transmission of resistance. Nonetheless, no detailed study has been done in East Africa to assess parasite clearance time following treatment with Artemisinin based combination therapies (ACTs).

In order to evaluate time to parasite clearance following treatment with AL, we conducted a detailed clinical trial with twenty blood sampling time points prior, during and after treatment. Detailed sampling allowed us to assess parasite clearance, and selection of Plasmodium falciparum multidrug resistance (Pfmdr) 1 N86Y and Plasmodium falciparum chloroquine resistance transporter (Pfcrt) K76T genes between different time points and its association with parasite clearance and recurrence. Furthermore, as a sensitive tool and an ideal early warning system, nested polymerase chain reaction (PCR) was used to assess parasite clearance and compare it with microscopic findings.