The World Health Organization (WHO) reported on Sunday three deaths linked to a possible outbreak of hantavirus, a disease that can cause acute respiratory syndrome, on a cruise ship in the Atlantic.

"The WHO has been informed of a public health event involving a cruise ship sailing in the Atlantic Ocean and is providing support," she told AFP.

The cruise ship, MV Hondius, was traveling from Ushuaia, Argentina, to Cape Verde. On Sunday, it was directly opposite the port of Praia, the capital of Cape Verde, an AFP photographer and videographer observed.

"To date, one case of hantavirus infection has been laboratory confirmed, and five other cases are suspected. Of the six people affected, three have died and one is currently in intensive care in South Africa," the UN agency said.

This passenger, a 69-year-old British national, is hospitalized in Johannesburg, said South African spokesman Foster Mohale, who reports to the Ministry of Health.

"Although rare, hantavirus can be transmitted from person to person and cause serious respiratory illness; it requires careful monitoring of patients, appropriate support and care," the WHO said.

"Extensive investigations are underway, including further laboratory analyses and epidemiological inquiries. Medical care and support are being provided to passengers and crew. Sequencing of the virus is also underway," she added.

According to a source familiar with the case who requested anonymity, a Dutch couple was among the three deceased. The third victim is believed to still be on board the ship.

A 70-year-old cruise passenger was the first to show symptoms. He died on board the ship and his body is currently on the island of Saint Helena, a British territory in the South Atlantic Ocean, according to the South African spokesperson.

His wife, aged 69, also fell ill on board the ship and was evacuated to South Africa: she died there at an undetermined date in a Johannesburg hospital, the same source said, which was unable to specify the nationality of the victims.

- Infected rodents -

According to the anonymous source familiar with the situation, discussions are underway to determine whether two other sick people will be placed in isolation in a hospital in Cape Verde, after which the ship could continue its journey to the Canary Islands, two or three days away at sea.

The WHO, for its part, indicates that it is "facilitating coordination" between countries and the ship's operators in order to "organize the medical evacuation of two passengers exhibiting symptoms." It also commends "the speed of the measures taken and the good coordination between all stakeholders."

The MV Hondius appears online on the websites of several travel agencies, particularly those based in Argentina and the United Kingdom. One of them offers a cruise departing from Ushuaia to Cape Verde, with stops at the islands of South Georgia and Saint Helena. It can accommodate approximately 170 passengers and has a crew of around 70.

Hantaviruses are transmitted to humans through infected wild rodents, such as mice or rats, which shed the virus in their saliva, urine, and feces. A bite, contact with these rodents or their droppings, or inhalation of contaminated dust can cause infection.

There are many types of hantavirus, which are distinguished by their geographical distribution and clinical presentation. According to the website of the Swiss Federal Office of Public Health (FOPH), "only one type of virus, which is extremely rare, can be transmitted from one human being to another."