Respiratory adenoviral infections in Taiwanese children: a hospital-based study.

BACKGROUND AND PURPOSE Adenoviruses are a common etiology of respiratory tract infections in children, with several serotypes responsible for most epidemic respiratory infections. This study examined the molecular epidemiology and clinical features of pediatric adenoviral infections in a 1-year period. METHODS From May 1999 to April 2000, virus specimens collected from children with respiratory tract infections were identified. The presence of adenovirus was confirmed by direct fluorescent staining, and viral types were determined by polymerase chain reaction sequencing. RESULTS Adenoviruses were identified from 272 children (mean +/- standard deviation age, 48.3 +/- 30.5 months), 227 (83.5%) of whom were aged 6 years or younger. Inpatients were younger than outpatients (44.1 +/- 30.7 months vs 53.0 +/- 29.4 months; p = 0.006). The commonest serotype identified was serotype 3 (164 patients; 60.3%), 73.1% of which were identified between September 1999 and January 2000. Serotype 3 was more common in inpatients (p = 0.015), while serotypes 1, 2, 5, and 6 were more common in outpatients (p = 0.021). Patients with pneumonia were younger than those with other infections (31.8 +/- 20.2 months vs 50.3 +/- 31.0 months; p = 0.001). Most of the children (90.1%) had fever for a mean of 3.80 +/- 2.65 days before seeing a doctor. The clinical manifestations were similar regardless of the serotype. CONCLUSIONS Adenovirus serotype 3 caused the most adenovirus infections in autumn and winter of 1999 to 2000. The children were mostly preschool age and required hospital admission.