A One Health investigation of a Crimean-Congo Hemorrhagic fever outbreak reveals high seropositivity in livestock in Lyantonde District, Uganda, 2024

Abstract

In January 2024, an outbreak of Crimean-Congo hemorrhagic fever (CCHF) was confirmed in Buyanja village, Lyantonde District, Uganda. Initially suspected to be anthrax, laboratory tests at the Uganda Virus Research Institute (UVRI) confirmed CCHF, prompting a One Health response. Five (5) human cases were confirmed through both Reverse Transcription Polymerase Chain Reaction(RT-PCR) and IgM Enzyme-Linked Immunosorbent Assay (ELISA) testing, all of which were associated with direct contact with livestock, particularly goats. Among the twenty-six goats sampled, 88% (23/26) tested positive for CCHFV-specific IgG antibodies, indicating prior exposure. All the goat samples were negative by PCR, suggesting no active infection at the time of testing. Molecular sequencing revealed viral strains clustering in the Africa II clade, with multiple S-segment lineages circulating. These findings support localized virus persistence in Lyantonde area and highlight occupational exposure risks in Uganda's cattle corridor. Strengthening One Health surveillance with emphasis on veterinary services integration is critical to CCHF control.