Three passengers have died on the cruise ship MV Hondius and others have been taken ill following an outbreak of the rare hantavirus.
Here is what we know so far about the ship, which had been crossing the Atlantic and is currently isolated off Cape Verde:
Who Is On Board?
There are more than 140 people on the MV Hondius, including more than 80 passengers from 15 countries, according to the ship's Dutch operator Oceanwide Expeditions.
The passengers including large groups from Britain, the United States, Spain and the Netherlands. Most of the crew are from the Philippines.
Three Deaths
A Dutch couple who had travelled around South America before boarding the ship in Argentina on April 1 were the first confirmed deaths.
The husband showed symptoms on April 6 and died on April 11. His body was taken off the ship on April 24 in Saint Helena, an island in the south Atlantic.
His wife, who was feeling unwell, also left the ship at Saint Helena. Her health deteriorated during an April 25 flight to Johannesburg and she died in hospital a day later, with hantavirus confirmed on May 4.
A German passenger who developed a fever on April 28, which became pneumonia, died on May 2. Her body is still on the ship.
Evacuees
A British passenger became ill on April 24 with signs of fever and pneumonia and was evacuated to South Africa, where he is in intensive care. Hantavirus was confirmed on May 2.
Two crew members, one British and one Dutch, also showed symptoms. They were evacuated on Wednesday along with a passenger who was showing no symptoms but has links to the German woman who died.
Swiss officials, meanwhile, confirmed on Wednesday another passenger who had left the cruise earlier was being treated in Zurich for hantavirus.
The Virus
The rare disease is usually spread from infected rodents, typically through urine, droppings and saliva.
Laboratory testing in South Africa and Switzerland confirmed the cases from the ship were the Andes strain of the hantavirus, the only one known to pass between humans.
There are no vaccines or specific medications for hantavirus.
Last year, the wife of Oscar-winning actor Gene Hackman died of hantavirus.
However, officials including WHO chief Tedros Adhanom Ghebreyesus said the overall public health risk from the current outbreak was low, as very close contact was needed for it to spread.
The Journey
The cruise from Ushuaia in Argentina began on April 1.
After South Georgia, Tristan da Cunha and other nearby islands, the vessel called at Saint Helena between April 22-24 and then Ascension Island on April 27.
It has been anchored off Praia, the capital of Cape Verde, since Sunday.
What Is Happening On Board?
The WHO said Tuesday passengers were being asked to isolate in their cabins while disinfection and other measures are being taken.
Where Might The Ship Go Next?
Cape Verde will not allow the ship to dock.
The WHO said the plan was for the ship to head north to Spain's Canary Islands for disinfection, risk assessment and a full epidemiological investigation.
Spain's health ministry has said the ship is expected in the Canaries in the next few days.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
