1. Division of Gastroenterology; Department of Medicine; Duke University Medical Center; Durham NC USA
2. Centro de Pesquisas Gonçalo Moniz; Fundação Oswaldo Cruz; Salvador Bahia Brazil
3. Section of Gastroenterology; Department of Medicine; Durham Veteran Affairs Medical Center; Durham NC USA
4. Foundation for Liver Research; Institute of Hepatology; London UK
5. Faculdade de Medicina; Universidade Federal de Minas Gerais; Belo Horizonte Minas Gerais Brazil
6. Centers for Disease Control and Prevention; Atlanta GA USA
7. Life Technologies; Durham NC USA
8. Núcleo de Doenças Infecciosas; Centro de Ciências da Saúde; Universidade Federal do Espírito Santo; Vitória Espírito Santo Brazil