Abstract / Summary
Abstract Background Acute Respiratory Infections (ARI) remains a significant burden on global health, particularly affecting children under five years old, primarily caused by viral pathogens, yet clinical data on viral etiology and outcomes in Latin America are scarce. This study aimed to describe the incidence of severe cases of ARI and other clinical outcomes across five major cities in Colombia in 2018, in children under five years old. Methods A descriptive, ecological study was conducted using extensive national health system databases to evaluate ARI cases requiring emergency care, hospitalization, or intensive care unit admissions from January 1st to December 31st, 2018, across major cities in Colombia. Incidence rates, etiological pathogens, and mortality outcomes were described. Additionally, a subgroup analysis stratified by age group was performed to explore correlations between clinical diagnoses, disease severity, and mortality. Results The age- and sex-adjusted incidence rate was 3,488 cases per 10,000 children/year in the five selected cities. The median age of the selected sample was 2 years, with younger children in the ICU group (median age 1 year) compared to the non-ICU group (median age 2 years) ( p < 0.001). Bacterial pneumonia was the most common diagnosis, and respiratory syncytial virus (RSV) was the leading viral etiology. The highest mortality rate was observed in children under 1 year of age (0.2%, p < 0.001), with bronchiolitis (0.3%, p < 0.001) and bacterial pneumonia (0.1%, p < 0.001) being the most frequent causes of death. ICU admissions had a mortality rate of 0.8% ( p < 0.001), while RSV was the most common viral etiology, with only one death reported. Conclusion In conclusion, this study reveals a significant burden of ARI in Colombian young children, with seasonal incidence peaks aligning with the rainy season. RSV predominated in ICU admissions, and bacterial pneumonia was highly incident. Targeted interventions, improved surveillance, and tailored healthcare strategies are essential to reduce the impact of ARI in this vulnerable population.