1. Hepatology Section, Division of Digestive Diseases, Department of Metabolism, Digestion and Reproduction, 10th Floor QEQM Wing, St Mary’s Hospital Campus, Imperial College London, South Wharf Street, LondonW2 1NY, England.
2. Department of Gastroenterology and Hepatology, Charité University Medical Center, Berlin, Germany.
3. Unité d'Épidémiologie des Maladies Émergentes, Institut Pasteur, Paris, France.