Spatio-temporal distribution of under-five malaria morbidity and mortality hotspots in Ghana, 2012 – 2017: a case for evidence-based targeting of malaria interventions

Abstract

Introduction: The spatiotemporal variation in malaria burden underpins the need for targeted malaria interventions. Despite the scale-up of malaria control interventions in Ghana, malaria remains the leading cause of hospital admissions and deaths among children below 5 years (U5). We described spatiotemporal distribution of U5 malaria morbidity and mortality from 2012 to 2017 to provide evidence for deployment of specific malaria interventions to regions of hotspots in Ghana. Methods: We conducted a retrospective review of district-level malaria surveillance data from 2012 to 2017. We obtained confirmed U5 malaria case and population data for all districts in Ghana, and computed yearly smoothed malaria incidence and mortality rates. Hotspot analysis was performed using GeoDa’s Global and Local Moran I tests of spatial autocorrelation. Results: Overall, 8,132,769 U5 malaria cases and 5,932 deaths were reported, with case fatality rate of 0.1%. Under-five malaria incidence increased from 16.4% in 2012 to 31.3% in 2017, and the mortality rate per 100,000 decreased from 30.2 in 2012 to 6.1 in 2017. We found variation in morbidity hotspots from 8 to 23 in the western, south-western and north-eastern areas of the country each year, and six persistent mortality hotspots in the north-eastern areas. Conclusion: Over the review period, U5 malaria morbidity increased while mortality decreased. Variability in morbidity hotspots occurred across the western and northern regions unlike persistence of mortality hotspots in the north-eastern region. We recommend that the National Malaria Control Program systematically deploys preventive and case management interventions to areas of hotspots and also conduct a further evaluation to identify the causes of high mortality in the northeastern areas.