Malaria patterns across altitudinal zones of Mount Elgon following intensified control and prevention programs in Uganda

Abstract

Background Malaria remains a major tropical vector-borne disease of immense public health concern owing to its debilitating effects in sub-Saharan Africa. In the recent past, the high altitude areas in Eastern Africa have been reported to experience dramatic cases of malaria. However, its patterns following intensified control and prevention interventions remains and the changing climate remains widely unexplored in these regions. This study thus analyzed malaria patterns across altitudinal zones of Mount Elgon, Uganda. Methods Times-series data on malaria cases (2011 - 2017) from five level III local health centers occurring across three altitudinal zones; low, mid and high altitude was utilized. Inverse Distance Weighted (IDW) interpolation regression and Mann Kendall trend test were used to analyze malaria patterns. Autoregressive Integrated Moving Average (ARIMA) model was used to project malaria patterns for a seven year period. Results On average, 66±69/1000 individuals suffered from malaria on a monthly basis. This was most pronounced in the months of May-August 89±88/1000 compared to the months of November-February (40±33/1000). Malaria patterns varied with season and altitude and declined over time across the three altitudinal zones. Observed cases, revealed an annual average of 587±750/1000; 345±321/1000 and 338±351/1000 cases in lower, mid and high altitudes respectively. Conclusions Despite observed decline in malaria cases across the three altitudinal zones, the high altitude zone became a malaria hotspot as cases variably occurred in the zone. The projections of malaria revealed declining patterns of malaria cases in all the altitudinal zones. Malaria control interventions thus ought to be strengthened and strategically designed to achieve no malaria cases across all the altitudinal zones. Integration of climate information within malaria interventions can also strengthen eradication strategies of malaria in such differentiated altitudinal zones.