CAPE TOWN -- South Africa's National Department of Health confirmed on Sunday evening that two people have died from an acute respiratory infection on board a cruise ship in the Atlantic Ocean.

The two individuals were on the polar cruise ship MV Hondius, operated by the Netherlands-based Oceanwide Expeditions, which was en route from Ushuaia in southern Argentina to Cape Verde.

According to earlier media reports, the first reported case, a 70-year-old passenger, died on board the ship, and his 69-year-old wife was evacuated to South Africa and later died at a hospital in Johannesburg.

A third person was hospitalized in intensive care in Johannesburg and tested positive for hantavirus. It was not immediately clear if the cases were linked.

"I can confirm that two people have demised from acute respiratory infection," Health Department spokesperson Foster Mohale told Xinhua.

"At this stage, no additional sick persons have been reported," Mohale said, adding that "no definitive diagnosis" had been made for the third case.

Hantavirus is a rare but potentially serious virus spread primarily through contact with infected rodents or their droppings, urine, or saliva.