Intra-urban variability of long-term exposure to PM2.5 and NO2 in five cities in Colombia

Rapidly urbanizing cities in Latin America experience high levels of air pollution which are known risk factors for population health. However, the estimates of long-term exposure to air pollution are scarce in the region. We developed intraurban land use regression (LUR) models to map long-term exposure to fine particulate matter (PM2.5) and nitrogen dioxide (NO2) in the five largest cities in Colombia. We conducted air pollution measurement campaigns using gravimetric PM2.5 and passive NO2 sensors for 2 weeks during both the dry and rainy seasons in 2021 in the cities of Barranquilla, Bucaramanga, Bogotá, Cali, and Medellín, and combined these data with geospatial and meteorological variables. Annual models were developed using multivariable spatial regression models. The city annual PM2.5 mean concentrations measured ranged between 12.32 and 15.99 µg/m3 while NO2 concentrations ranged between 24.92 and 49.15 µg/m3. The PM2.5 annual models explained 82% of the variance (R2) in Medellín, 77% in Bucaramanga, 73% in Barranquilla, 70% in Cali, and 44% in Bogotá. The NO2 models explained 65% of the variance in Bucaramanga, 57% in Medellín, 44% in Cali, 40% in Bogotá, and 30% in Barranquilla. Most of the predictor variables included in the models were a combination of specific land use characteristics and roadway variables. Cross-validation suggests that PM2.5 outperformed NO2 models. The developed models can be used as exposure estimate in epidemiological studies, as input in hybrid models to improve personal exposure assessment, and for policy evaluation.

Clínica de la malaria complicada debida a P. falciparum Estudio de casos y controles en Tumaco y Turbo (Colombia)

ANTECEDENTES Y PROBLEMA: son muy pocos los estudios latinoamericanos sobre malaria por Plasmodium falciparum (P falciparum) complicada y se requiere estudiarla para identificar un patrón propio. OBJETIVOS. Identificar las complicaciones presentes en pacientes de Tumaco (Nariño) y Turbo (Antioquia) en Colombia, con malaria por P falciparum. MÉTODOS. Diseño de casos y controles. Se aplicaron los criterios diagnósticos de complicación OMS-2000 (Organización Mundial de la Salud). RESULTADOS. Se captaron 64 casos (con malaria por P. falciparum complicada) y 135 controles (con malaria por P. falciparum no complicada). El tiempo de evolución de la enfermedad (promedio 5,6 días en los casos y 5,9 en los controles) y la frecuencia de síntomas fueron similares en ambos grupos (p>0,05), pero la dificultad respiratoria y la ictericia fueron más frecuentes en los casos que en los controles (p