A boat with 54 migrants on board drifted off the West African coast for ten days without water or food on board after an engine failure.
When the Mauritanian coast guard discovered the ship on August 16, only seven people were still alive, as the UN Refugee Agency (UNHCR) and the UN Organization for Migration (IOM) reported in Geneva on Wednesday.
The refugees were on their way to the Canary Islands.
The island of Fuerteventura is about 100 kilometers from Morocco on the African mainland.
The IOM and UNHCR did not provide any information about where the boat left on August 3 and how far it had drifted.
The Mauritanian Coast Guard found the survivors on Monday.
They were brought to Nouadhibou about 850 kilometers south of Fuerteventura.
According to the IOM and UNHCR, more than 350 people have died on the refugee route to the Canary Islands this year.
A good 8,000 would have reached the islands.