[1] McGill Univ, Dept Pediat, Montreal, PQ, Canada
[2] McGill Univ, Dept Epidemiol Biostat & Occupat Hlth, Montreal, PQ, Canada
[3] Univ Montreal, Dept Microbiol Infect Dis & Immunol, Montreal, PQ, Canada
[4] Univ British Columbia, Providence Hlth Care, CHEOS, Vancouver, BC, Canada
[5] Virginia Commonwealth Univ, Dept Pediat, Richmond, VA USA
[6] Univ Calgary, Dept Pediat, Calgary, AB, Canada
[7] Univ Ottawa, Dept Pediat, Ottawa, ON, Canada
[8] McGill Univ, Hlth Ctr, Res Inst, Montreal, PQ, Canada
[9] Univ British Columbia, Dept Med, Vancouver, BC, Canada
[10] Univ Montreal, Dept Pediat, Montreal, PQ, Canada