Conference Abstract | Volume 8, Abstract ELIC2025139 (Poster 032) | Published: 30 Jul 2025
Moshood Olamide Lateef1,&, Abideen Titilope Aransi1,2, Dauda Nathaniel3
1Virology and Molecular Diagnostics Unit, International Institute of Tropical Agriculture, Ibadan, Nigeria, 2Department of Virology, College of Medicine, University of Ibadan, Ibadan, Nigeria, 3Department of Crop Sciences, Faculty of Agriculture, University of Nigeria, Nsukka Nigeria
&Corresponding author: Moshood Olamide Lateef, Virology and Molecular Diagnostics Unit, International Institute of Tropical Agriculture, Ibadan, Nigeria. Email: m.lateef@cgiar.org
Received: 25 Apr 2025, Accepted: 09 Jul 2025, Published: 30 Jul 2025
Domain: Infectious Disease Epidemiology
Keywords: Lassa, evolutionary, relationship, diversity, lineage VI
©Moshood Olamide Lateef et al. Journal of Interventional Epidemiology and Public Health (ISSN: 2664-2824). This is an Open Access article distributed under the terms of the Creative Commons Attribution International 4.0 License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Cite this article: Moshood Olamide Lateef et al., Genome diversity and understanding the evolutionary relationship of Lassa virus. Journal of Interventional Epidemiology and Public Health. 2025;8(ConfProc5):00176. https://doi.org/10.37432/JIEPH-CONFPRO5-00176
Lassa fever is an acute viral haemorrhagic illness caused by the Lassa virus (LASV), primarily transmitted through contact with the multimammate rat. The disease is endemic to West Africa, where it is estimated to affect approximately two million individuals annually. Previous diversity studies on LASV relied on partial or complete gene sequences containing undetermined nucleotides (“N”), which can compromise the accuracy and reliability of phylogenetic and evolutionary analyses. To enhance the robustness and credibility of genomic investigations, this study aims to comprehensively assess the genetic diversity of LASV using full-length open reading frames (ORFs) encoding the polymerase, nucleoprotein, and glycoprotein, all free from “N.”
LASV nucleotide sequences were retrieved from GenBank. Sequences exhibiting ≥90% pairwise identity and originating from the same country were clustered into groups. From each group, representative sequences with no “N” within the polymerase ORF were selected. For each chosen L segment (polymerase), the corresponding S segment (nucleoprotein and glycoprotein) from the same viral isolate was also selected, provided it contained no “N.” Genetic variability among the selected ORFs was assessed using the Sequence Demarcation Tool (SDT). Multiple sequence alignment was conducted using MAFFT (Multiple Alignment using Fast Fourier Transform), and phylogenetic inference was performed with IQ-TREE2.
The study revealed genetic variability of up to 32%, 26%, and 25% in the polymerase, nucleoprotein, and glycoprotein ORFs, respectively. LASV strains are classified into seven distinct lineages. Notably, lineage VI exhibited a phylogenetic relationship with all other LASV lineages and also showed evolutionary relatedness to other Old World arenaviruses.
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