Prevalence and genetic variability of occult hepatitis B virus in a human immunodeficiency virus positive patient cohort in Gondar, Ethiopia. oleh Nishi H Patel, Vanessa Meier-Stephenson, Meaza Genetu, Debasu Damtie, Ebba Abate, Shitaye Alemu, Yetework Aleka, Guido Van Marle, Kevin Fonseca, Carla S Coffin, Tekalign Deressa