Trend and Spatial Geographical Distribution of the Reemergence of Diphtheria in Plateau State, North-Central Nigeria

Background: Diphtheria, an infectious disease caused by Corynebacterium diphtheriae, is a major worldwide health problem due to its high incidence and prevalence, especially among children. Nigeria is among the African countries with the highest reported cases in the North-central geopolitical zone, with Plateau State being particularly affected. Objective: This study aimed to identify Diphtheria trends and spatial geographic distribution in Plateau State, Nigeria. Methodology: The study used a retrospective cross-sectional and ecological design to understand the temporal trends and spatial distribution of diphtheria cases across Plateau State from January 2015 to December 2024. The sample size was determined by the number of diphtheria cases reported by the WHO from 2015 to 2024. Purposive sampling was used based on the location of suspected, confirmed, and death cases in 17 Local Government Areas (LGAs). Data was extracted from WHO databases and visualised using ArcGIS software. The study adhered to ethical guidelines, ensuring unbiased analysis and open disclosure. Data were analysed using SPSS 25.0 and ArcGIS, and the Chi-square test was used to examine the relationship between LGAs and classification and vaccination at a significance level of 0.05. Results: The study revealed that Kenam had the highest incidence of suspected, confirmed, and fatal cases among the 441 LGAs, followed by Barkin-Ladi and Jos-North. The lowest incidence was found in Jos-East, Kanke, and Langtang-South. The most confirmed cases were found in Kenam, followed by Jos-East, Kanke, and Langtang-South. The research also found a significant correlation between local government areas and diphtheria incidences, with 59.2% of Kanam's population vaccinated. Conclusion: There is a significant trend and spread of suspected cases of Diphtheria in Plateau State, with a few confirmed cases. Kanem LGA recorded high suspicion, confirmed, vaccinated, and uncertainty about people's vaccinated status. It is therefore recommended that WHO and PSHMB take prompt action by immunising those who are not afflicted, educating the public about diphtheria symptoms, re-introducing booster shots, identifying symptomatic individuals early, and reducing geographic spread factors.