Hantavirus: Mystery Illness Kills 3 Cruise Ship Passengers Off Coast Of Africa

The World Health Organization (WHO) has confirmed that seven cases of hantavirus has been identified, with two laboratory confirmed cases of hantavirus and five suspected cases.

On May 2 2026, a cluster of passengers with severe respiratory illness aboard a cruise ship was reported to the WHO.

The ship is carrying a total of 147 individuals, including 88 passengers and 59 crew members, with the onboard passengers and crew representing 23 nationalities. As of Monday, seven cases have been identified, including three deaths, one critically ill patient and three individuals reporting mild symptoms.

“Illness onset occurred between 6 and 28 April 2026 and was characterised by fever, gastrointestinal symptoms, rapid progression to pneumonia, acute respiratory distress syndrome and shock. Further investigations are ongoing,” WHO said.

The organisation said the outbreak is being managed through a coordinated international response, and includes in-depth investigations, case isolation and care, medical evacuation and laboratory investigations.

“Human hantavirus infection is primarily acquired through contact with the urine, faeces, or saliva of infected rodents. It is a rare but severe disease that can be deadly. Although uncommon, limited human to human transmission has been reported in previous outbreaks of Andes virus (a specific species of hantavirus).”

WHAT WE KNOW SO FAR

Laboratory testing conducted in South Africa confirmed hantavirus infection in one patient who is critically ill and in intensive care. On May 3, one additional death was reported. A further three suspected cases remain on board. As of Monday, a total of seven (two confirmed and five suspected) cases, including three deaths, have been reported.

The vessel departed Ushuaia, Argentina, on April 1 2026 and followed an itinerary across the South Atlantic, with multiple stops in remote and ecologically diverse regions, including mainland Antarctica, South Georgia, Nightingale Island, Tristan da Cunha, Saint Helena, and Ascension Island.

It is worth noting that the extent of passenger contact with local wildlife during the voyage, or prior to boarding in Ushuaia remains undetermined. As of Monday, the vessel is moored off the coast of Cabo Verde.

BREAKDOWN OF THE CASES

Case 1: An adult male developed symptoms of fever, headache, and mild diarrhoea on April 6 2026 while on board the ship. By April 11, the case developed respiratory distress and died on board on the same day. No microbiological tests were performed. The body of the passenger was removed from the vessel to Saint Helena (a British Overseas Territory) on April 24.

Case 2: An adult female, who was a close contact of case 1, went ashore at Saint Helena on April 24 2026 with gastrointestinal symptoms. She subsequently deteriorated during a flight to Johannesburg, South Africa, on April 25. She later died upon arrival at the emergency department on 26 April. On Monday, the case was subsequently confirmed by PCR with hantavirus infection. Contact tracing for passengers on the flight has been initiated.

Cases 1 and 2, had travelled in South America, including Argentina, before they boarded the cruise ship on April 1 2026.

Case 3: An adult male presented to the ship’s doctor on April 24 2026 with febrile illness, shortness of breath and signs of pneumonia. On 26 April, his condition worsened. He was medically evacuated from Ascension to South Africa on April 27, where he is currently hospitalised in an Intensive Care Unit (ICU). Laboratory testing on an extensive respiratory pathogen panel was negative; however, polymerase chain reaction (PCR) testing confirmed hantavirus infection on May 2 2026. Serology, sequencing and metagenomics are ongoing.

Case 4: An adult female, with presentation of pneumonia, died on May 2 2026. The onset of symptoms was on April 28, with fever and a general feeling of being unwell.

Three suspected cases have reported high fever and/or gastrointestinal symptoms and remain on board.

HOW HANTAVIRUS IS TRANSMITTED

• Primarily through contact with infected wild rodents
• Inhalation of airborne particles from rodent urine or droppings
• Consuming food contaminated by rodent urine or droppings
• Rarely through bites or scratches

EARLY SYMPTOMS OF HANTAVIRUS

• Fever and chills
• Headache and dizziness
• Intense muscle aches