The World Health Organization (WHO) was notified on 2 May 2026 of a cluster of severe respiratory illnesses aboard a Dutch-flagged cruise vessel. The ship carried a total of 147 passengers and crew, and by 4 May 2026 authorities had identified seven people with illness, including two laboratory-confirmed hantavirus infections, five suspected cases, and three deaths. Illness onset among affected people ranged from 6 to 28 April 2026, and presentations included fever, gastrointestinal complaints and a rapid progression to pneumonia, acute respiratory distress syndrome (ARDS) and shock. The event triggered coordinated medical evacuation, case isolation and intensive laboratory work.
The vessel began its journey in Ushuaia, Argentina on 1 April 2026 and visited remote ecological sites across the South Atlantic, including mainland Antarctica, South Georgia, Nightingale Island, Tristan da Cunha, Saint Helena and Ascension Island. As of 4 May 2026 the ship was moored off the coast of Cabo Verde. Onboard were 88 passengers and 59 crew representing 23 nationalities. Investigators are working to determine whether exposures occurred ashore, during wildlife contact on port calls, or via other routes during the voyage.
Case timeline and clinical descriptions
Health teams have documented detailed timelines for several cases. Case 1 was an adult male who developed fever, headache and mild diarrhoea on 6 April 2026, progressed to respiratory distress and died aboard on 11 April 2026; no microbiological tests were taken before the body was transferred to Saint Helena on 24 April 2026. Case 2, a close contact of Case 1, went ashore at Saint Helena on 24 April 2026 with gastrointestinal symptoms, deteriorated on a flight to Johannesburg, South Africa on 25 April 2026, and died on 26 April 2026; this case was confirmed by PCR on 4 May 2026. Case 3 presented on 24 April 2026, was evacuated from Ascension to South Africa on 27 April 2026 and tested positive by PCR on 2 May 2026. Case 4 had symptom onset on 28 April 2026 and died on 2 May 2026. Three additional suspected cases with fever or gastrointestinal complaints remain under evaluation onboard.
Laboratory work and ongoing investigations
National reference laboratories and international partners have been mobilized. The National Institute for Communicable Diseases (NICD) in South Africa performed confirmatory testing, including reverse transcriptase PCR, and announced positive results on 2 May 2026 and 4 May 2026 for two patients. Further testing—serology, sequencing and metagenomic analysis—is ongoing to characterise the virus. Additional specimens are being sent with WHO support to the Institut Pasteur de Dakar for parallel testing. Investigators are also tracing contacts from flights and port calls to identify potential secondary cases and exposure events.
Public health response and risk assessment
Authorities from Cabo Verde, the Netherlands, Spain, South Africa and the United Kingdom have coordinated actions including isolation of cases, medical evacuation, logistic support and sample collection. The WHO has activated three-level coordination mechanisms and shared information with National IHR Focal Points globally. At present WHO assesses the risk to the global population as low, while continuing epidemiological monitoring and case finding. Response teams are balancing ship sanitation, individual clinical care and cross-border public health measures to limit further spread.
Advice for passengers, crew and clinicians
WHO guidance for those on board emphasizes frequent hand hygiene, physical distancing where practicable and active symptom monitoring for 45 days. Individuals with respiratory symptoms are asked to self-isolate, practice respiratory etiquette and wear medical masks. Crew should undertake careful environmental cleaning, avoid dry sweeping (which can aerosolize contaminated dust) and ensure good ventilation. Healthcare workers should apply standard precautions plus transmission-based precautions during close contact; for aerosol-generating procedures, airborne precautions are recommended. Diagnostic tools include ELISA for IgM/IgG and RT–PCR for viral RNA; clinical management is primarily supportive with early ICU referral when needed.
Implications for travelers and disease control
Hantavirus infection typically arises after exposure to rodent urine, faeces or saliva, and most cases are linked to rural or sylvatic settings. The possibility of human-to-human transmission is rare but has been documented with the Andes virus in South America under conditions of close and prolonged contact. Public health messaging should stress rodent control, safe food storage, wet-cleaning methods, and prompt care-seeking for suggestive symptoms. For most routine tourism activities the risk of exposure is low, but enhanced vigilance is warranted for ecotourism itineraries that include remote landings or wildlife contact. WHO and national authorities will continue to update guidance as investigations and laboratory results evolve.
