After showing signs of improvement, Jose Salvador Alvarenga's health has deteriorated.
Alvarenga, who said he was lost at sea for 13 months, returned to a hospital Thursday to be intravenously fed, said Christian Clay-Mendoza, a top Mexican trade official.
"Doctors say he's severely dehydrated and low on vitamins and minerals," he said.
Alvarenga, an El Salvadoran who had been living in Mexico, washed ashore on the Marshall Islands eight days ago. Earlier this week, his condition improved enough that he was released from a hospital.
Doctors said Alvarenga's limbs have started to swell, and they can't seem to keep him hydrated.
But he did manage to leave the hospital briefly Thursday to make a few comments to the media.
Bewildered by all the cameras, he thanked the government and people of the Marshall Islands for their care and friendship. After his minute-long remark, officials whisked him back to the hospital.
Plans for his repatriation to El Salvador on Friday have now been postponed due to his health.
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