(Adds health minister's comments, cruise lines, Dutch ship)
NASSAU, Bahamas, Sept 5 (Reuters) - An international relief effort gathered pace on Thursday to help stunned residents of the Bahamas, where the health minister predicted a "staggering" death toll from Hurricane Dorian, now churning northward off the coast of South Carolina.
Aerial video of the Abaco Islands in the northern Bahamas worst hit by the then-Category 5 hurricane showed widespread devastation, with the harbor, shops, workplaces, a hospital and airport landing strips damaged or decimated.
The death toll from Dorian was officially 23 while authorities continued to retrieve and register bodies, Health Minister Duane Sands told local media. But he said the final toll would be far higher.
"Let me say that I believe the number will be staggering," he was quoted by The Nassau Guardian as telling Guardian radio. "I have never lived through anything like this and I dont want to live through anything like this again."
Sands said he has asked for help from the World Health Organization and others. The United Nations has estimated more than 76,000 people were in need of humanitarian relief after the most damaging storm ever to hit the island nation.
The U.N. World Food Programme (WFP) said on Thursday it was organizing an airlift from Panama of storage units, generators and prefab offices for two logistics hubs, as well as satellite equipment for emergency responders, and has bought eight metric tonnes of ready-to-eat meals.
The U.N. agency has allocated $5.4 million to a three-month emergency operation to support 39,000 people, said Hervé Verhoosel, senior WFP spokesperson.
"In a first phase, WFP will focus on the immediate procurement and distribution of up to 85 MT of ready-to-eat meals for the most affected communities," Verhoosel said.
A flight from the U.S. Agency for International Development landed early on Thursday with enough relief supplies to help 31,500 people, bringing hygiene kits, water containers and buckets, plastic sheeting and chain saws.
Also arriving was a disaster assistance response team (DART) plane that included a fire and rescue team to help in the search for survivors, USAID's Office of Foreign Disaster Assistance said on Twitter.
Total insured and uninsured losses in the Bahamas amounted to $7 billion, including buildings and business interruptions, according to a preliminary estimate by Karen Clark & Co, a consultancy that provides catastrophic modeling and risk management services.
With telephones down in many areas, residents posted lists of missing loved ones on social media. One Facebook post by media outlet Our News Bahamas had 2,500 comments, mainly listing lost family members.
One survivor on the Abaco Islands, Ramond King, said he watched as swirling winds ripped the roof off his house, then churned to a neighbor's home to pluck the entire structure into the sky.
"'This can't be real, this can't be real'," King recalled thinking. "Nothing is here, nothing at all. Everything is gone, just bodies."
The Netherlands' ambassador to the United Nations tweeted the country was sending two naval ships with supplies from St Maarten, a Dutch island about 1,100 miles (1,770 km) southeast of the Bahamas.
A British Royal Navy vessel was providing assistance, and Jamaica was sending a 150-member military contingent to help secure Abaco and Grand Bahama, officials said.
Volunteers also ferried supplies to the islands in a flotilla of small boats.
Cruise lines responded as well.
The Bahamas Paradise Cruise Line said it would transport first responders, medics and journalists for free to Freeport on Thursday, returning to Florida on Friday with any Bahamians who have documents to enter the United States.
"It's a humanitarian trip. We're also taking donations that have arrived in the port (in Palm Beach)," said Francisco Sanchez, a sales representative for the cruise line.
Royal Caribbean's Empress of the Seas said it was delivering 10,000 meals of chicken, rice and fruit to Grand Bahama.
POSSIBLE RECORD SURGE
Dorian killed one person in Puerto Rico before hovering over the Bahamas for two days with torrential rains and fierce winds that whipped up 12- to 18-foot (3.7- to 5.5-meter) storm surges.
On Thursday, the storm was barreling north-northeast just off the southeastern U.S. coast, moving at about 7 miles per hour (11 kph), with maximum sustained winds fluctuating between 110 and 115 mph (175-185 kph), between a Category 2 and Category 3 storm on the five-point Saffir-Simpson wind scale.
The storm was about 50 miles (80 km) east-southeast of flood-prone Charleston, South Carolina, at 11:30 a.m. EST (1530 GMT), the U.S. National Hurricane Center said.
The forecast called for the storm to move northeast along North Carolinas Outer Banks, a popular coastal vacation spot, by Friday afternoon and then out to sea. The NHC also added a tropical storm warning for coastal Virginia.
Parts of the Carolinas could get 6 to 10 inches (15 to 25 cm) of rain, with some areas topping out at 10-15 inches (25 to 38 cm). Storm surge was forecast at 5 to 8 feet (1.5 to 2.4 meters) in Myrtle Beach, South Carolina.
More than 2.2 million people in Florida, Georgia, North Carolina and South Carolina had been ordered to evacuate, although Florida avoided a direct hit.
More than 239,000 homes and businesses in the U.S. Southeast were without power, according to local electric companies.
(Reporting by Nick Brown in Nassau, Bahamas, additional reporting by Nick Carey in Charleston, South Carolina, Alex Dobuzinskis in Los Angeles, Rebekah Ward in Mexico City, Andrew Hay in Taos, New Mexico and Rich McKay in Atlanta, writing by Scott Malone and Sonya Hepinstall; Editing by Bernadette Baum and Cynthia Osterman)