Study of Karolinska Institutet and Washington University polyomaviruses in tonsil, adenoid, throat swab and middle ear fluid samples

Abstract

Aim: To study prevalence of Karolinska Institutet (KI) and Washington University (WU) polyomavirus (PyV) in 100 tonsils, 100 adenoids, 146 throat swab and 15 middle ear fluid samples collected from 146 patients (120 children and 26 adults), to analyze the sequence of  noncoding control region (NCCR) and complete WUPyV genomes. Materials & methods: Viruses were detected by quantitative real-time PCR. The NCCRs and WUPyV genomes were sequenced and analyzed. Results: The frequency of WUPyV and KIPyV DNA was 27 and 11% in adenoids, 4 and 3% in tonsils, 4.1 and 1.4% in throat swab samples, respectively. The WUPyV DNA was detected in one middle ear fluid sample as well. The WUPyV NCCRs showed mutations which may alter the putative transcription factor binding sites. Phylogenetic analysis revealed three clades of WUPyV. Conclusion: Tonsils and adenoids might be site of virus replication and/or persistence, and WUPyV may invade into the middle ear.