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 {CI}, 52%-60%]). Respiratory syncytial virus (RSV) was detected in 260 participants (34% [95% CI, 31%-38%]) and other respiratory viruses were detected in 219 participants (29%; 95% CI, 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% CI, 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% CI, 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. JAMA. 2010;303(20):2051-2057 www.jama.com