1 Medical Research Council (MRC) Unit, Banjul, The Gambia; Unité d'Épidémiologie des Maladies Émergentes, Institut Pasteur, Paris 75015, France. Electronic address: yusuke.shimakawa@gmail.com.
2 Laboratoire de Bactériologie-Virologie, CHU Aristide le Dantec, Dakar, Senegal.
3 International Agency for Research on Cancer (IARC), Lyon, France.
4 Department of Hepatology, Imperial College London, London, UK.
5 Medical Research Council (MRC) Unit, Banjul, The Gambia; Department of Hepatology, Imperial College London, London, UK.