[1] Univ Med Ctr Utrecht, Dept Paediat Immunol, Wilhelmina Childrens Hosp, NL-3508 AB Utrecht, Netherlands
[2] Univ Groningen, Dept Rheumatol & Clin Immunol, Univ Med Ctr Groningen, Groningen, Netherlands
[3] Manchester Royal Infirm, Vaccine Evaluat Unit, Hlth Protect Agcy NW, Manchester M13 9WL, Lancs, England
[4] Univ Manchester, Inflammat Sci Res Grp, Sch Translat Med, Manchester M13 9WL, Lancs, England
[5] Natl Inst Publ Hlth & Environm RIVM, Ctr Infect Dis Control Netherlands, Bilthoven, Netherlands
[6] Univ Paris Sud, Dept Paediat, CeReMAI, CHU Bicetre, F-94275 Le Kremlin Bicetre, France
[7] Univ Gothenburg, Dept Paediat, Gothenburg, Sweden
[8] Childrens Univ Hosp Charite Berlin, German Rheumatism Res Ctr Berlin, Epidemiol Unit, Berlin, Germany
[9] Univ Genoa, Dept Paediat, Ist Giannina Gaslini, Genoa, Italy
[10] Newcastle Upon Tyne Hosp NHS Fdn Trust, Dept Paediat Immunol, Newcastle Upon Tyne, Tyne & Wear, England
[11] Univ Sao Paulo, Dept Paediat, Immunol & Rheumatol Unit, Sch Med Ribeirao Preto, Sao Paulo, Brazil
[12] Univ Leipzig, Dept Paediat, Municipal Hosp St Georg Leipzig, Acad Teaching Hosp, Leipzig, Germany