Polyomaviruses KI and WU in children with respiratory tract infection

The polyomaviruses KI (KIPyV) and WU (WUPyV) have recently been discovered in specimens from patients with respiratory tract infections. To analyze the frequency and clinical impact in a cohort of pediatric patients in a German University Children's Hospital. Nasopharyngeal aspirates or bronchoalveolar lavage specimens of 229 children with acute respiratory tract infection were screened for KIPyV and WUPyV using polymerase chain reaction-based methods. KIPyV was detected in 2 (0.9%) and WUPyV in 1 (0.4%) patients, without co-infections with other respiratory viruses but with co-detection of CMV, EBV and HHV 6 in one immunocompromised patient. Only a very small proportion (1.3%) of positive samples for KIPyV and WUPyV was documented in this study; the clinical relevance of these viruses remains unclear and requires further evaluation.