[1] Amsterdam Acad Med Ctr, Dept Infect Dis, Div Internal Med, Ctr Trop Med & Travel Med,AMC, Meibergdreef 9,F4-217, NL-1105 AZ Amsterdam, Netherlands
[2] Univ Cape Town, Dept Pediat & Child Hlth, MRC Unit Child & Adolescent Hlth, Red Cross War Mem Childrens Hosp, Klipfontein Rd, ZA-7701 Cape Town, South Africa
[3] Charite Univ Med Berlin, Dept Pediat Pneumol & Immunol, Augustenburger Pl 1, D-13353 Berlin, Germany
[4] Anna Louisa Karsch Str 2, D-10178 Berlin, Germany
[5] Univ Cape Town, Dept Stat Sci, ZA-7701 Cape Town, South Africa
[6] Univ Amsterdam, Med Lib, Acad Med Ctr, Meibergdreef 9, NL-1105 AZ Amsterdam, Netherlands
[7] Univ Utrecht, Cochrane Netherlands, Julius Ctr Hlth Sci & Primary Care, Univ Med Ctr Utrecht, Univ Weg 100, NL-3584 CG Utrecht, Netherlands