Respiratory syncytial virus, adenoviruses, and mixed acute lower respiratory infections in children in a developing country.

There is growing evidence suggesting greater severity and worse outcomes in children with mixed as compared to single respiratory virus infections. However, studies that assess the risk factors that may predispose a child to a mixture of respiratory syncytial virus (RSV) and adenoviral infections, are scarce. In a retrospective cohort study, the study investigated the epidemiology of RSV and adenovirus infections and predictors of mixed RSV-adenoviral infections in young children hospitalized with acute lower respiratory infection in Bogota, Colombia, South America, over a 2-year period 2009-2011. Of a total of 5,539 children admitted with a diagnosis of acute lower respiratory infection, 2,267 (40.9%) who were positive for RSV and/or adenovirus were selected. Out the total number of cases, 1,416 (62.5%) infections occurred during the 3-month period from March to May, the first rainy season of Bogota, Colombia. After controlling for gender, month when the nasopharyngeal sample was taken, and other pre-existing conditions, it was found that an age greater than 6 months (OR:1.74; CI 95%:1.05-2.89; P = 0.030) and malnutrition as a comorbidity (OR:9.92; CI 95%:1.01-100.9; P = 0.049) were independent predictors of mixed RSV-adenoviral infections in the sample of patients. In conclusion, RSV and adenovirus are significant causes of acute lower respiratory infection in infants and young children in Bogota, Colombia, especially during the first rainy season. The identified predictors of mixed RSV-adenoviral infections should be taken into account when planning intervention, in order to reduce the burden of acute lower respiratory infection in young children living in the country.