1. Division of Otorhinolaryngology, Department of Clinical SciencesUppsala University Uppsala Sweden
2. Department of Ear, Nose and ThroatÖstersunds hospital, Jämtland/Härjedalen County Council, Uppsala University Uppsala Sweden
3. Division of Clinical Virology, Department of Clinical MicrobiologyUppsala University Uppsala Sweden
4. Division of Otorhinolaryngology, Department of Surgical SciencesUppsala University Uppsala Sweden
5. Division of PathologyUppsala University Uppsala Sweden