Belachew, M. | bioRxiv Science

bioRxiv2026

Functional validation of the Plasmodium falciparum K13 C580Y mutation in recently collected Ethiopian isolates

Recent genomic investigation in Ethiopia identified the first detection of the Plasmodium falciparum kelch13 (K13) C580Y substitution in the Horn of Africa. To assess its functional impact, we introduced C580Y into two recently collected Ethiopian clinical isolates using CRISPR-Cas9 genome editing. Ring-stage survival assays showed significantly elevated in vitro dihydroartemisinin (DHA) survival in edited parasites relative to isogenic controls, demonstrating that C580Y confers artemisinin tolerance in contemporary Ethiopian parasite genetic backgrounds.

microbiology↗

bioRxiv2024

Molecular epidemiology of Ascaris lumbricoides following multiple rounds of community-wide treatment: who infects whom?

Control and elimination of the parasite Ascaris lumbricoides relies on mass administration using a limited number of anti-helminthics. Whilst these programs have reduced the infection intensity and prevalence within many endemic regions transmission is poorly understood, with reinfection commonly occurring following cessation of treatment. Here, we utilise genomic data to understand parasite transmission within and between households in a community and the genomic impact of repeated MDA. We sequenced 54 whole-genomes from individuals in a longitudinal cohort epidemiological study of transmission and drug treatment extending over 6 years. We found that fine-scale population structure exists in spatially distinct clusters of infected individuals with reinfection occurring within or between geographically close households. This observation helps inform the policy of future control in low prevalence settings suggesting more targeted treatment of infection hotspots We found evidence of positive selection acting on members of gene families previously implicated in reduced drug efficacy but detect no high frequency of impactful variants. As efforts to eliminate A. lumbricoides intensify, our study provides a foundation for genomic surveillance to help identify both who infects whom and the impact of repeated drug treatment.

genomics↗

bioRxiv2024

Genomic characterization of a unique population of Leishmania tropica in a new emerging focus of cutaneous leishmaniasis in Somali region of Ethiopia

We sequenced Leishmania tropica genomes directly from eight human skin samples collected in a newly emerging focus of cutaneous leishmaniasis in Somali region, Ethiopia. We found a new variant with unique genomic signatures of drug resistance. Genomic homogeneity in the sampled population demonstrates the occurrence of a L. tropica outbreak.

microbiology↗