Evidence of partial artemisinin resistance in malaria endemic lake region, Busia county, Western, Kenya

Abstract

Malaria remains a key health and economic problem particularly in sub-Saharan Africa. The emergence of artemisinin resistance (ART-R) parasite strains poses a serious threat to the control and elimination of this scourge. This is because ART remains the first-line treatment drug in the majority of malariaendemic regions in Sub-Saharan Africa. P. falciparum ART resistance has been linked to mutations in the Kelch – 13 propeller gene (k13) of the Plasmodium falciparum. Single nucleotide polymorphisms in the K-13 region have been associated with delayed parasite clearance in vivo and in vitro. These mutations serve as vital molecular markers for tracking the emergence and dispersion of resistance. Recently, there have been increasing reports of the emergence and spread of P. falciparum ART-R parasites in the Eastern Africa region. This necessitates continued surveillance to best inform mitigation efforts. This study investigated the presence of K-13 mutations in the parasite population in Busia County, Kenya, a known malaria-endemic region. Two hundred twenty-six participants with microscopically confirmed uncomplicated malaria were recruited for this study. They were put under directly observed treatment with Artemether-Lumefantrine (AL), and microscopy repeated after 24 hours. P. falciparum DNA from samples showing the lowest 24-hour relative parasite clearance underwent targeted amplification of the K-13 gene using a semi-nested PCR approach, followed by Sanger sequencing. The recently validated ART-R nonsynonymous mutation C469Y was identified in 3% (n = 3) of the samples suggesting it could have had an impact on clinical parasite clearance 24 hours post-AL administration. Our findings highlight the need for continuous surveillance of AL resistance in western Kenya and the region to determine the spread of ART-R and inform containment.