Development of a Multiplex Isothermal Amplification Point-of-Care Platform for Simultaneous Detection of Priority Livestock Pathogens in Field Settings in Nigeria

This dissertation develops and validates an original multiplex isothermal nucleic acid amplification point-of-care (POC) diagnostic platform for simultaneous rapid detection of six priority livestock pathogens under field conditions in Nigeria, addressing the critical gap between laboratory diagnostic capacity and the need for rapid, accurate, pen-side disease diagnosis in resource-limited Nigerian veterinary settings. Current field diagnosis of livestock diseases in Nigeria depends predominantly on clinical examination and historical outbreak data, with laboratory confirmation delayed by transport logistics, cold chain constraints, and limited laboratory capacity. The dissertation employs a four-phase methodology: bioinformatic primer and probe design for LAMP or NASBA-based detection of NDV, FMDV, PPRV, CBPP, African swine fever virus, and Rift Valley fever virus using conserved genomic targets; analytical validation of individual and multiplexed assays against panel DNA and RNA standards; cross-reactivity and inhibition testing using field-relevant sample matrices; and field validation at 30 sites across all six geopolitical zones, comparing POC platform results to gold-standard laboratory PCR. The study produces an original diagnostic innovation, the NiVetPlex POC Platform, which achieves analytical sensitivity within one log unit of gold-standard PCR for all six targets and delivers results in 45 minutes from sample collection without laboratory infrastructure. The dissertation provides original contributions to veterinary diagnostic technology and a field implementation roadmap for national deployment. Keywords: point-of-care diagnostics, isothermal amplification, livestock pathogens, field diagnostics, Nigeria.