Evidence of Partial Artemisinin Resistance in Malaria Endemic Lake Region, Busia County, Western, Kenya

Abstract

<title>Abstract</title> 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 malaria-endemic regions in Sub-Saharan Africa. <italic>P. falciparum</italic> ART resistance has been linked to mutations in the Kelch – 13 propeller gene (k13) of the <italic>Plasmodium falciparum</italic>. Single nucleotide polymorphisms in the K-13 region have been associated with delayed parasite clearance <italic>in vivo</italic> and <italic>in vitro</italic>. 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 <italic>P. falciparum</italic> 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. <italic>P. falciparum</italic> 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.