aDepartment of Microbiology, Division of Laboratory Medicine, Oslo University Hospital, Oslo, Norway

bDivision of Infectious Diseases, Department of Medicine Huddinge, Karolinska Institutet, Stockholm, Sweden

cViro-Immunology Research Unit, Department of Infectious Diseases, Rigshospitalet, Copenhagen University Hospital

dDepartment of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen

eDepartment of Surgical Gastroenterology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark

fMinneapolis Veterans Affairs Healthcare System

gUniversity of Minnesota, Minneapolis, Minnesota, USA

hInstitute of Clinical Medicine, University of Oslo

iResearch Institute of Internal Medicine, Division of Surgery, Inflammatory Diseases and Transplantation

jSection of Clinical Immunology and Infectious Diseases, Department of Rheumatology, Dermatology and Infectious Diseases, Oslo University Hospital, Oslo, Norway

Correspondence to Marius Trøseid, MD, PhD, Professor, University of Oslo and Oslo University Hospital, Oslo 0424, Norway. Tel: +47 92440240; e-mail: [email protected]