<b>Molecular Epidemiology of</b><b> Pneumococcal Meningitis, Northern Ghana: </b><b>Serotypes </b><b>Distribution </b><b>and</b><b> </b><b>R</b><b>esistance-</b><b>A</b><b>ssociated genes</b><b>.</b>

AbstractBackground: Ghana is part of the African meningitis belt with seasonal records of meningitis resulting in significant case fatalities annually. Streptococcus pneumoniae (pneumococcus) meningitis outbreaks, previously uncommon are gaining prominence in current meningitis outbreaks despite the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13).Methods: The cerebrospinal fluid (CSF) samples for this study were collected from patients in all age groups with suspected meningitis in the five northern regions (Northern, Upper East, North East, Savannah and Upper West) for the 2022/2023 and 2023/2024 meningitis seasons A real-time PCR multiplex assay was performed directly on CSF samples to simultaneously identify Streptococcus pneumoniae, Neisseria meningitidis and Haemophilus influenzae. Multiplex PCR was conducted on pneumococcal isolates targeting serogroup/serotype-specific genetic regions. Testing was also performed for resistance-associated genes such as Tetracycline resistance determinant (tetM) followed by Erythromycin ribosomal methylase B (ermB), Macrolide efflux proteinA/B and Penicillin-binding protein 2b. A chi-square test of independence was used to assess the association between variables while a simple binary logistic regression was used to assess predictor of infectivity. Spatial maps were used to illustrate the temporal distribution of serotype groups across the five regions.Ethics StatementThis study was conducted as part of the seasonal meningitis outbreak response in Ghana. The Institutional Review Board of Ghana Health Service reviewed and approved the protocol (Approval number GHS-ERC 024/01/23). Additional approval was obtained from the Committee on Human Research, Publication and Ethics of the Kwame Nkrumah University of Science and Technology with (Reference ID: CHRPE/AP/029/23). Informed consent was waived because samples were collected under routine outbreak surveillance procedures, and all data were anonymized prior to analysis. The study posed minimal risk to participants and was essential for timely public health action. All procedures complied with the ethical standards of the institutional research committees and the principles of the Declaration of HelsinkiResults: Two hundred and ten (210) patients reported suspected meningitis in the five northern regions during the period. The Upper West region recorded the highest 109 (51.90%) while North East region recorded the least 13 (6.19%). Majority of the total suspected meningitis cases was recorded between the ages of 15 and 24 altogether contributing 14.3% (30/210). Of the 210 cases, 90 (42.7%) pneumococcal cases were detected by Realtime multiplex_ PCR. Of the 90 confirmed pneumococci detections, the vast majority of serotype identified belonged to serotype 1 (41.1%), serotype 33AF (18.9%) and serotype 23A/23B (14.4%).Twelve (12) case fatalities (13.3%) were identified and these were mostly associated with serotypes 1, 23A/23B and 33AF. The dominant resistance-associated gene identified in the pneumococcal population was tetM (47.8%; 43/90), followed by ermB (23.3%; 21/90), Penicillin-binding protein 2b (22.2%; 20/90) and mefA/B (15.6%; 14/90). Serotypes that expressed multiple resistance-associated genes included 33A/F, 23A/23B, 1, 38 and 24.Conclusion: The recurrence of pneumococcal serotype 1 meningitis outbreaks along with the presence of multiple resistance-associated genes carrying serotypes highlights the need for strengthening meningitis surveillance, diagnostic capacity building and reassessment of the current vaccination programme in high-risk countries.