[1] UNIV ROTTERDAM HOSP, SOPHIA CHILDRENS HOSP, DIV PEDIAT INFECT DIS & IMMUNOL, NL-3000 CB ROTTERDAM, NETHERLANDS
[2] ERASMUS UNIV ROTTERDAM, DEPT EPIDEMIOL & BIOSTAT, ROTTERDAM, NETHERLANDS
[3] UNIV AMSTERDAM, EXPT & CLIN IMMUNOL LAB, AMSTERDAM, NETHERLANDS
[4] NETHERLANDS RED CROSS, BLOOD TRANSFUS SERV, CENT LAB, AMSTERDAM, NETHERLANDS