Abstract
BACKGROUND: Bronchiolitis is considered as the most frequent lower respiratory tract infection in infants and young children. This disorder is marked by acute inflammation, edema, damage of epithelial cells lining small airways, and augmentation of mucus production. OBJECTIVE: The goal of the study was to identify agents triggering bronchiolitis in the State of Qatar. MATERIALS AND METHODS: A cross-sectional retrospective study was performed at Hamad Medical Corporation, the only tertiary and academic medical center in the State of Qatar. The study included infants and young children aged 0-24 months who were admitted to our pediatric ward with diagnosis of acute bronchiolitis (2010-2012). RESULTS: Eight hundred thirty-five infants and young children met the study inclusion criteria with mean age at diagnosis of 3.61±3.56 months. Respiratory virus real-time polymerase chain reaction was performed on 769 (92.0%) of the participants. Respiratory syncytial virus (RSV) was positive in 352 (45.7%) children admitted with clinical bronchiolitis. In addition, no viruses were identified in 142 (18.4%) of those admitted, and respiratory viruses other RSV were found in 275 (35.7%) of the children. Our investigations and observations show that there has been a steady and periodic seasonal variation in the RSV rate over the study period. A seasonal trend for the RSV (detected by respiratory virus real-time polymerase chain reaction) rate was evident, showing annual peaks in the months of October, November, December, and January, with a significant test for seasonality (test statistics [T]=3.15, P=0.009). CONCLUSION: In countries with desert hot weather, bronchiolitis might affect children throughout the year. Our results suggest that the combination of date regarding uninterrupted RSV seasonality can provide guidance for health care planning and application of RSV prevention scheme, such as extending the palivizumab immunoglobulin series.