Molecular Detection of Crimean-Congo Haemorrhagic Fever Virus in Livestock and Ticks in Borno State, North East Nigeria: A One Health Approach

Crimean-Congo haemorrhagic fever is a tick-borne viral zoonosis associated with high case fatality rates in humans, and livestock serve as important amplification hosts for the causative nairovirus, creating a critical interface for human infection risk. This study applied a One Health approach to detect CCHF virus in livestock and Hyalomma ticks in Borno State, North East Nigeria. Whole blood samples were collected from 150 cattle, 100 goats, and 100 sheep at abattoirs and pastoral camps in Maiduguri and surrounds. Hyalomma ticks were collected from livestock and from vegetation by flagging. All samples were tested by CCHF virus-specific RT-PCR targeting the S gene segment. Positive samples were confirmed by nested PCR and partial sequencing. Seroprevalence of anti-CCHF IgG was determined in 60 abattoir workers by ELISA. CCHF viral RNA was detected in 4.2% of cattle, 2.0% of goats, and 1.0% of sheep. Hyalomma rufipes and Hyalomma truncatum were the predominant tick species collected. Tick positivity rate was 8.4%. Phylogenetic analysis placed Borno sequences within the African clade IV, related to strains from Sudan and Cameroon. Anti-CCHF IgG seroprevalence in abattoir workers was 11.7%. The study confirms active CCHF virus circulation in Borno State and recommends establishment of human CCHF surveillance, tick control on livestock, provision of personal protective equipment for abattoir workers, and development of a One Health zoonotic disease response framework for North East Nigeria. Keywords: Crimean-Congo haemorrhagic fever, RT-PCR, Hyalomma ticks, zoonosis, One Health