MAJURO, Marshall Islands - A castaway who says he survived 13 months adrift in the Pacific appears to be suffering post-traumatic stress syndrome, a doctor said Saturday, as officials confirmed he had been living in Mexico illegally.
Jose Salvador Alvarenga, a fisherman from El Salvador, washed up on a remote Pacific atoll over a week ago, telling a remarkable story of floating 12,500 kilometres (8,000 miles) from Mexico in his 24-foot boat after the engine broke.
He initially appeared to be in good spirits and reasonable health, but he has been in and out of hospital since being brought to the Marshalls capital Majuro last Monday.
At a media conference on Thursday, the 37-year-old was sullen and uncomfortable, mumbling a short thank-you to people in the Marshall Islands before departing the venue clutching two men for support.
Franklyn House, a retired American doctor working with the California-based Canvasback Missions group in the Marshall Islands, has observed and spoken with Alvarenga several times since his arrival, although he is not the attending physician.
Fluent in Spanish, House said he believes Alvarenga is suffering post-traumatic stress syndrome because of the change in his demeanour from Monday when he was engaged with doctors to being withdrawn on Thursday.
"The first couple of days he was in the hospital, he was engaged and normal," House told AFP. "Thursday he showed signs of post-traumatic stress."
A diplomat from El Salvador's embassy in Japan, Diego Dalton, met with the castaway and "confirmed that the health of Mr Alvarenga is broken", the country's foreign ministry said in a statement.
"His physical condition has to improve for him to begin the return trip, which does not have a defined date," it added.
Alvarenga was due to leave on Friday for El Salvador via Hawaii, but he was told to rest and doctors have scheduled a follow-up appointment for Monday.
This means the earliest he is expected to depart is on a flight to Honolulu that night. The next flight is not until Wednesday.
Alvarenga, who said he survived on a diet of raw fish and birds while drinking turtle blood, urine and rainwater, is also suffering from dehydration and back problems.
Swelling in his legs and the back pain lessened on Friday when he was discharged from Majuro Hospital, said a nurse who asked not to be named.
"He was readmitted Thursday because of pain in his back and legs," the nurse said.
"He was not really coherent. But he was talking clearly when he was discharged Friday."
While Alvarenga is from El Salvador, he began his ill-fated shark fishing trip from Mexico, where he had lived for years.
Manila-based Mexican diplomat Christian Clay Mendez, who jetted in to help handle Alvarenga's repatriation, said he had been in Mexico illegally for 15 years, which is why he would go back to El Salvador.
But he said that if after his return to El Salvador, he "goes through the proper channels, I'm sure that our embassy people in El Salvador would be more than willing to assist in getting him to Mexico legally".
"We'd be willing to look into that," he added.
Media interest in his ordeal has been global, and the El Salvador foreign ministry said Alvarenga now wanted to be left alone.
"Following the events that he lived through, Mr Jose Salvador Alvarenga has asked for privacy to overcome this experience," the ministry's communications chief Irene Sanchez told AFP.
"He wants privacy and does not want to see the media" when he returns, she said, adding that Alvarenga's family had also asked to be left alone.