The 28-year-old man, identified as Evan Muncie, was found in the wreckage of a market where he sold rice, his family told staff at a University of Miami field hospital. He suffered from extreme dehydration and malnutrition, but did not appear to have significant crushing injuries, the doctors said.
"He was emaciated. He hadn't had anything in quite some time. He had open wounds that were festering on both of his feet," said Dr. Mike Connelly, of the university's Project Medishare.
The people who brought him to the hospital said they found the man while digging out the marketplace, Connelly said.
The discovery came nearly a month after the magnitude-7.0 earthquake that devastated Port-au-Prince on January 12. More than 200,000 deaths have been blamed on the quake.