[1] London Sch Hyg & Trop Med, London WC1, England
[2] Karnataka Hlth Promot Trust, Bangalore, Karnataka, India
[3] Univ Manitoba, Winnipeg, MB, Canada
[4] St Johns Res Inst, Bangalore, Karnataka, India
[5] Univ London Imperial Coll Sci Technol & Med, London, England
[6] CHU Quebec, Ctr Rech, Quebec City, PQ, Canada