Neuro-Ophthalmological Manifestations of Endemic Infectious Diseases in North East Nigeria: A Multi-Centre Prospective Investigation

North East Nigeria represents a unique epidemiological intersection of endemic infectious diseases including cerebrospinal meningitis, viral encephalitides, Lassa fever, and trypanosomiasis, all of which produce neuro-ophthalmological sequelae that remain systematically unstudied. This multi-centre prospective investigation characterises the neuro-ophthalmological manifestations of endemic infectious diseases in North East Nigeria over a four-year study period. A prospective observational study will be conducted at the neurology and infectious disease units of University of Maiduguri Teaching Hospital, Federal Medical Centre Nguru, and Federal Teaching Hospital Gombe. All patients with confirmed endemic infectious disease diagnoses will undergo a standardised neuro-ophthalmological evaluation including visual acuity, colour vision, visual fields by confrontation, pupillary examination, extraocular motility assessment, fundus examination for disc and retinal changes, and visual evoked potentials where available. Cerebrospinal fluid analysis and neuroimaging findings will be correlated with ophthalmic data. Multivariable analysis will identify disease, host, and treatment factors predicting specific neuro-ophthalmological outcomes. Meningitis-related optic atrophy, Lassa fever optic neuritis, and trypanosomiasis-associated uveitis are documented in isolated case reports but have not been prospectively characterised in a multi-centre study from north-eastern Nigeria. The region's security context and humanitarian crisis compound the under-documentation of these conditions. This study generates foundational evidence for clinical practice and infectious disease programme integration of neuro-ophthalmological screening. Recommendations will include mandatory neuro-ophthalmic assessment for all hospitalised infectious disease patients and ophthalmology rotation for infectious disease residency training. Keywords: neuro-ophthalmology, endemic infections, Lassa fever, meningitis, North East Nigeria