Viral etiology of severe pneumonia among Kenyan infants and children

Context: Pneumonia is the leading cause of childhood death in sub-Saharan Africa. Comparative estimates of the contribution of causative pathogens to the burden of disease are essential for targeted vaccine development. Objective: To determine the viral etiology of severe pneumonia among infants and children at a rural Kenyan hospital using comprehensive and sensitive molecular diagnostic techniques. Design, Setting, and Participants: Prospective observational and case-control study during 2007 in a rural Kenyan district hospital. Participants were children aged 1 day to 12 years, residing in a systematically enumerated catchment area, and who either were admitted to Kilifi District Hospital meeting World Health Organization clinical criteria for severe pneumonia or very severe pneumonia; (2) presented with mild upper respiratory tract infection but were not admitted; or (3) were well infants and children attending for immunization. Main Outcome Measures: The presence of respiratory viruses and the odds ratio for admission with severe disease. Results: Of 922 eligible admitted patients, 759 were sampled (82% [median age, 9 months]). One or more respiratory viruses were detected in 425 of the 759 sampled (56% [95% confidence interval {Cl}, 52%-60%]). Respiratory syncytial virus (RSV) was detected in 260 participants (34% [95% Cl, 31%-38%]) and other respiratory viruses were detected in 219 participants (29%; 95% Cl, 26%-32%), the most common being Human coronavirus 229E (n=51 [6.7%]), influenza type A (n=44 [5.8%]), Parainfluenza type 3 (n=29 [3.8%]), Human adenovirus (n=29 [3.8%]), and Human metapneumovirus (n=23 [3.0%]). Compared with well control participants, detection of RSV was associated with severe disease (5% in control participants; adjusted odds ratio, 6.11 [95% Cl, 1.65-22.6]) while collectively, other respiratory viruses were not associated with severe disease (23% in control participants; adjusted odds ratio, 1.27 [95% Cl, 0.64-2.52]). Conclusion: In a sample of Kenyan infants and children admitted with severe pneumonia to a rural hospital, RSV was the predominant viral pathogen. ©2010 American Medical Association. All rights reserved.