Residents of the hard-hit Florida Keys returned to inspect damaged homes and businesses that were largely without electricity and communications in the wake of the deadly storm.
Categorized as one of the most powerful Atlantic storms on record when it rampaged through the Caribbean, Irma killed more than 60 people, officials said.
At least 23 people died in Florida and nearby states, and destruction was widespread in the Keys, where Irma made initial US landfall on Sunday and became the second major hurricane to strike the mainland this season.
Two elderly residents were found dead at the Rehabilitation Center of Hollywood Hills and three later died at a hospital, Broward County Mayor Barbara Sharief told reporters on Wednesday.
Some residents were evacuated from the facility early Sunday morning and some reportedly awoke sick at the center, which had been without air conditioning for a few days.
Authorities barred re-entry to most of the Keys to allow more time to restore electricity and medical service and bring water, food and fuel. Some 10,000 Keys residents stayed put when the storm hit and may ultimately need to be evacuated, according to officials.
"I don't have a house. I don't have a job. I have nothing," said Mercedes Lopez, 50, whose family fled north from the Keys town of Marathon on Friday and rode out the storm at an Orlando hotel, only to learn their home was destroyed, along with the gasoline station where Lopez worked.
"We came here, leaving everything at home, and we go back to nothing," Lopez said. Four families from Marathon including hers planned to venture back on Wednesday to salvage what they could.
The Keys were largely evacuated by the time Irma barreled ashore as a Category 4 hurricane with sustained winds of up to 130 mph (215 km/hour).
Initial damage assessments found that 25 percent of homes there were destroyed and 65 percent suffered major damage, Federal Emergency Management Agency administrator Brock Long said.