Two decades of malaria in Colombia: changing epidemiology, spatial patterns, and health inequalities, 2001–2024

Introduction Malaria is a significant public health problem in Colombia. Over the past two decades, environmental changes, internal migration, and gold mining expansion have been linked to variations in transmission dynamics, highlighting the need for updated epidemiological analyses. Objective To describe the epidemiological patterns of malaria in Colombia between 2001 and 2024 and explore its association with gold mining during the period of 2018–2020. Methods A retrospective, descriptive, observational study was conducted using data from the National Institute of Health of Colombia and the Ministry of Mines and Energy (2018–2020). The annual parasite index (API) and proportions by species were calculated, and demographic variables such as sex, age, and ethnicity were also analyzed. Results 1, 671, 460 cases of malaria were reported (average API = 1.59 per 1, 000 inhabitants). Plasmodium vivax was the predominant species (59.2%), and the incidence of P. falciparum increased from 2014 onward. Approximately 70% of the cases were concentrated in Chocó, Antioquia, Córdoba, and Nariño. The cases predominated in men (60%) and in people between 5 and 44 years of age. Between 2018 and 2020, the area affected by illegal gold mining increased from 59, 255 to 69, 198 hectares, with a positive and significant correlation between the mining area and malaria cases (ρ = 0.606–0.662; p < 0.05). Conclusions Between 2001 and 2024, the epidemiology of malaria in Colombia showed a geographically concentrated transmission pattern, along with changes in distribution by species and sociodemographic characteristics. From 2018 to 2020, a positive association was observed between mining activity and malaria cases, suggesting a possible role of environmental transformation in transmission dynamics. These findings suggest that territorial, social, and environmental factors are relevant for guiding malaria control in the country.