Expansion of the Plasmodium falciparum Kelch13 R622I Mutation in Northwest Ethiopia.

According to the World Health Organization, almost two-thirds of the Ethiopian population is at risk of contracting malaria, where infection with Plasmodium falciparum accounts for approximately 60% of cases today. The risk of artemisinin resistance spreading from southeast Asia to Africa is a major concern. We conducted a 28-day in vivo efficacy trial of artemether-lumefantrine (Coartem) for treatment of uncomplicated malaria (n = 97) in the Gondar area, northwest Ethiopia, from 2017 to 2018. Our results confirmed 100% adequate clinical and parasitologic response, with no parasites observed at day 3 by microscopy. Further analysis of day 0 samples showed the expansion of a Kelch13 mutation R622I to 9.5% from 2.4% of isolates reported 3 years earlier. Closer examination of the R622I mutation in vitro is warranted.