Do you know of this maneating reptile?

i have heard of a reptilian creature in the brazilian rainforest that is big enough to eat people. i heard about it from a friend that saw a special on national geographic. the program had to do with an explorer or a scientist who was doing research i believe when he got bit by the poisonous reptile. it followed him until he just collapsed. i know its a sad tale. he filmed himself before dying to. villagers found the cam eventually but there were no signs of him or anything else. so does anybody out there know?