[1] Imperial Coll London, Div Integrat Syst Med & Digest Dis, Dept Surg & Canc, London, England
[2] MRC Unit Gambia, Hepatitis Dept, Dis Control & Eliminat, Fajara, Gambia
[3] CRCL, INSERM, Lyon, France
[4] Inst Pasteur, Unite Epidemiol Malad Emergentes, Paris, France
[5] Imperial Coll London, Fac Med, London, England
[6] IARC, Lyon, France
[7] Minist Hlth, Natl Publ Hlth Labs, Kotu, Gambia
[8] MRC Unit Gambia, Fajara, Gambia
[9] INSERM, Lyon, France