Role of human polyomaviruses in respiratory tract disease in young children.

KI virus was detected in respiratory secretions of 8/367 (2.2%) symptomatic and 0/96 asymptomatic children (p = 0.215). WU virus was detected in 26/367 (7.1%) symptomatic and 6/96 (6.3%) asymptomatic children (p = 1.00). These human polyomaviruses may not independently cause respiratory tract disease in young children.