Differences in the Incidence of Malaria between Internally Displaced People and General Population of Colombia from 2007 to 2016

Abstract

Background: Malaria has been described among the most frequently reported parasitic diseases among refugees and internally displaced populations (IDPs) in Africa and Asia. There is a lack of studies about it in Latin America, including Colombia, the country with the highest number of IDPs in the world and also endemic for malaria. Methods & Materials: This ecological study assessed incidence and its differences, on malaria between general population and IDPs in Colombia and its departments (32) during 2007–2016. Epidemiological data was collected from the National Surveillance System (SIVIGILA-SISPRO), retrieving the codes for malaria in both populations. We estimated malaria incidence rates on both populations (cases/100,000 pop), using reference population of the IDPs (official record of the Secretary of Social Welfare) and the general population (from the national statistics institute, DANE). Incidence rates ratios were calculated comparing both populations. Results: In general population, 573,098 cases of malaria occurred (66% due to P. vivax) (1,237.19 cases/100,000 pop, 95%CI 1,234.0–1,240.0) while 13,655 among IDPs (70% due to P. vivax) (5,034.37 cases/100,000 pop, 95%CI 4,952.0–5,117.0). Malaria was 4.1 times higher among IDPs than in general population (p < 0.05) (ranging from 2.12 times in 2007 to 8.17 in 2016). Malaria mortality rate among general population was 0.32 deaths/100,000 pop and 1.84 among IDPs, being 5.81 times higher (p < 0.05). The difference by species, showed for Plasmodium malariae, 0.47 cases/100,000 pop in the general population and 4.06 among the internally displaced (8.62 times higher). A lower difference was observed for Plasmodium falciparum, 395.49 cases/100,000 pop among the general population and 1375.19 among internally displaced persons (3.48 times more). Conclusion: This study showed a significantly higher incidence of malaria among internally displaced persons, compared to the general population in the same territories, including also higher occurrence of complicated disease. This has relevant implications for screening, diagnosis and management among IDPs, especially in still highly endemic areas. More studies are required to improve the understanding of tropical diseases among vulnerable populations, as well to provide better medical interventions and for the development of public policies in countries, such as Colombia, with IDPs and in the context of post-conflict era.