Trends and spatial patterns of malaria incidence and intervention coverage in Bibiani Anhwiaso Bekwai Municiality, Western North Region, Ghana, 2015-2023

Introduction: Ghana is transitioning from a malaria-endemic country into elimination. While some districts have advanced into the pre-elimination phase, others remain classified as high-burden zones. Bibiani Anhwiaso Bekwai Municipality is classified as a high-burden area despite scale-up of interventions. We assessed temporal trends and sub-municipality differences in malaria incidence and intervention coverage from 2015–2023. Methods: We conducted a longitudinal secondary analysis of routine malaria surveillance data from the DHIMS II and Ghana Malaria Interventions System, 2015–2023. Temporal trends in monthly cases were assessed using Negative Binomial regression, while segmented fixed-effects linear regression was used to examine sub-municipal incidence and key intervention coverages (LLINs, IPTP and malaria testing). Results: Malaria incidence declined by 44% from 2015-2023 (465 to 261 per 1,000), equivalent to an average annual reduction of 8% (IRR = 0.92, 95% CI: 0.90–0.94). Seasonal peaks occurred mainly in May–August, alongside occasional off-season surges, with July incidence about 30% higher than January (IRR = 1.30, 95% CI: 1.03–1.65). Bibiani sub-municipality consistently recorded the highest malaria incidence, reflecting its persistently lower intervention coverage. At the 2019 baseline, the composite coverage of key malaria interventions in Bibiani sub-municipality was 66.4% (95% CI: 58.5–74.4), compared with significantly higher levels in Anhwiaso (+11.1 points), Bekwai (+9.7), and Chirano (+10.0). Correspondingly, incidence was significantly lower in Bekwai sub-municipality (β = –307.3, 95% CI: –464.8 to –149.9) and Anhwiaso (β = –196.0, 95% CI: –353.4 to –38.5) relative to Bibiani, while Chirano and Awaso also showed lower but non-significant differences. Conclusion: Malaria incidence in Bibiani Anhwiaso Bekwai Municipality declined substantially between 2015 and 2023. However, seasonal peaks and off-season surges persisted. Despite overall progress, Bibiani sub-municipality consistently recorded the highest incidence and lagged in intervention uptake. The Municipal health directorate should prioritize Bibiani sub-municipality as a focus area for improving coverage of malaria interventions.