"If you don't pull them out in one hour, in that golden hour, there's really a very low chance of survival,'' he said.
Those with other illnesses, whose health depends on medications, also face grim chances, Chiampas said.
"You see a lot of different scenarios where we've had some really miraculous saves and people have survived under horrible conditions.," said Dr. Christopher Colwell, an emergency medicine specialists at the University of California, San Francisco. "They tend to be younger people and have been fortunate enough to find either a pocket in the rubble or some way to access needed elements like air and water.''
After the 2011 Japan earthquake and tsunami, a teenager and his 80-year-old grandmother were found alive after nine days trapped in their flattened home. The year before, a 16-year-old Haitian girl was rescued from earthquake rubble in Port-Au-Prince after 15 days.