[1] Royal Childrens Hosp Melbourne, Childrens Canc Ctr, Parkville, Vic, Australia
[2] Peter MacCallum Canc Ctr, Dept Infect Dis & Infect Control, East Melbourne, Australia
[3] Univ Fed Sao Paulo, Dept Pediat, Pediat Oncol Inst IOP GRACC, Sao Paulo, Brazil
[4] Univ York, Alcuin Coll, Ctr Reviews & Disseminat, York YO10 5DD, N Yorkshire, England
[5] Leeds Teaching Hosp Trust, Reg Dept Paediat Haematol Oncol, Leeds, W Yorkshire, England