Detection of novel Pegivirus C genome in an unexplained febrile outbreak, Gombe State, Nigeria, 2024 by enhanced mNGS approach

OBJECTIVES: In July 2024, an outbreak of acute febrile illness occurred in Chassi village, Gombe State, Nigeria, affecting over 30 individuals, primarily children, with symptoms including fever, jaundice, abdominal pain, and mucosal bleeding. The cause remained unidentified after conventional diagnostics excluded known viral hemorrhagic fevers, malaria, and bacterial infections. This study aimed to investigate the potential etiologic agent behind the outbreak using unbiased genomic techniques. METHODS: We employed a metagenomic next-generation sequencing (mNGS) strategy with viral enrichment to analyze serum samples from 22 symptomatic patients. A novel complete 9.3 kb genome of Pegivirus C (GOMBE-017-2025) was reconstructed and phylogenetically compared to global sequences. Detection was validated using targeted PCR and Sanger sequencing. Environmental and microbial testing were conducted on local water sources. RESULTS: Pegivirus C was consistently detected in all 22 samples. The reconstructed genome showed 92.7% identity to a 2018 Nigerian strain and clustered with West African isolates. PCR and sequencing confirmed its presence. Environmental and bacterial sources were ruled out as causative agents. CONCLUSION: The uniform detection of Pegivirus C in this localized outbreak raises concern over its potential pathogenic or co-pathogenic role. These findings support the need for further investigation into its transmission dynamics, tropism, and clinical relevance.