Poster Presentation 25th International Pathogenic Neisseria Conference 2026

Epidemiological patterns and surveillance gaps in primary health care-level epidemic response during the 2025 Neisseria meningitidis serogroup C outbreak in Sokoto State, northern Nigeria.   (#079)

Ikechukwu Nnaji 1 2 , Abiodun Egwuenu 3 , Chinedu Okoroafor 4 , Abdulganiyu Yusuf 5 , Nuhu D Aliyu 5 , Aminu A Dogondaji 5 , Auwalu Musa 5 , Juliet Namugenyi 6 , Iliya D Cheshi 7 , Charles C Korie 8 , MacDonald S Maduabuchi 9 , Cynthia C Onyemuze 2 , Maimuna Ahmed 2 , M'ember Chagu 2 , Shamsu M Bello 10 , Michael O Popoola 8 , Joy M Ajodo 8 , Enoch P Fasulu 11 , Eugene S Bwede 8 , Nengak P Danladi 8 , Amos Dangana 8 , James C Avong 8 , Olajumoke Babatunde 8 , Emmanuel I Eze 3
  1. School of Public Health , Miva Open University, Abuja, Federal Capital Territory, Nigeria
  2. NCDC National Reference laboratory, Nigeria Centre for Disease Control and Prevention, Abuja, Federal Capital Territory, Nigeria
  3. Planning, Research and Statistics, Nigeria Centre for Disease Control and Prevention, Abuja, Federal Capital Territory, Nigeria
  4. Health Promotion and Prevention, Nigeria Centre for Disease Control and Prevention, Abuja, Federal Capital Territory, Nigeria
  5. Public Health and Epidemiology, Sokoto State Ministry of Health, Sokoto, Nigeria
  6. Field Epidemiology Training Program, Nigeria Centre for Disease Control and Prevention, Abuja, Federal Capital Territory, Nigeria
  7. Surveillance and Epidemiology, Nigeria Centre for Disease Control and Prevention, Abuja, Federal Capital Territory, Nigeria
  8. NCDC National Reference laboratory, Nigeria Centre for Disease Control and Prevention, Abuja, Federal Capital Territory, Nigeria
  9. Medical Laboratory Sciences, University of Nigeria , Nsukka, Enugu, Nigeria
  10. Vaccine Campaign, National Primary Health Care Development Agency, Abuja, Federal Capital Territory, Nigeria
  11. Diagnostics, APIN-Public Health Initiatives, Abuja, Federal Capital Territory, Nigeria

Introduction 

Cerebrospinal meningitis (CSM) remains a public health challenge in the African meningitis belt that spans more than 20 countries, of which Nigeria is one, with Neisseria meningitidis as a leading causative agent. The country experiences recurrent outbreaks, particularly in northern regions such as Sokoto State. Primary healthcare centers (PHCs) are the first point of care and integral part of Nigeria’s health system; however, gaps in surveillance, laboratory confirmation, and timely diagnosis persist. We present the report and findings of our study during the 2025 CSM outbreak response in Sokoto State.

Methods

This study was conducted from March to June 2025 across fourteen affected local government areas in Sokoto State. A total of 845 patients, 456 (54%) males and 389 (46%) females, who met the case definition for CSM, were enrolled. Standardized case investigation forms (CIF) were used to collect demographic and epidemiological data with corresponding cerebrospinal fluid (CSF) samples, where feasible. Samples were tested using real-time polymerase chain reaction at the NCDC-National Reference Laboratory. Results were analyzed using SPSS Version 16 and interpreted for informed public health decisions and interventions.

Results 

Out of the 845 suspected cases identified, only 113 (13.4%) had their CSF samples tested. Among the tested samples, 74 (65.5%) were confirmed positive for Neisseria meningitidis serogroupC (NmC), with a case fatality rate (CFR) of 63.7% (72/113), because of limited sample collection, with a high proportion of cases not having laboratory results due to inadequate lumbar puncture and laboratory access. Poor documentation of vaccination history was observed, with only 3.6% (30/845) of the cases having recorded vaccination status, of whom 86.7% (26/30) were unvaccinated. Infection trends showed activity throughout the period of study, with a peak observed from epidemiological weeks 10 - 17.

Conclusion

Our findings highlight critical gaps in surveillance, laboratory testing, sample collection, and vaccine coverage during the meningococcal outbreak, resulting in an increased number of cases and deaths, hence a CFR above the WHO threshold. Strengthening PHCs for improved surveillance, robust vaccination campaigns/coverage, and training of clinicians on lumbar puncture are recommended and essential for effective control of N. meningitidis outbreaks in Nigeria.