The MV Hondius outbreak is the first confirmed hantavirus cluster aboard a commercial cruise vessel and the most internationally complex Andes virus event on record. This article compiles every confirmed event from the ship’s departure to the current status.
The Voyage Begins — March 20, 2026
MV Hondius, a 350-passenger ice-strengthened expedition ship operated by Oceanwide Expeditions, departed Ushuaia, Argentina, on a 21-day Antarctic cruise. The manifest listed approximately 200 passengers from 13 nationalities, accompanied by around 80 crew members. The route included landings on the Antarctic Peninsula, South Georgia, and the Falkland Islands.
No unusual health events were reported during the Antarctic landfall phase. Biosafety briefings focused on the standard protocols — prohibiting soil disturbance and contact with wildlife — but hantavirus screening was not standard practice for Antarctic voyages.
First Illness — Around April 15, 2026
Approximately 26 days after departure, a passenger of Dutch nationality developed a febrile illness with severe headache and myalgia during the Drake Passage return crossing. The ship’s medical officer initially assessed the case as influenza-like illness, consistent with the confined-space transmission that is common aboard cruise ships.
Within 48 hours, the patient’s condition deteriorated rapidly, with progressive respiratory distress consistent with Hantavirus Pulmonary Syndrome (HPS). The ship’s emergency medical team initiated supplemental oxygen and contacted maritime health authorities.
The patient was evacuated by helicopter to a hospital in Buenos Aires, Argentina, where they died shortly after admission. Post-mortem testing later confirmed Andes virus by RT-PCR.
Second Death — April 26, 2026
A second passenger, a British national, developed symptoms approximately 10 days after the first case. Despite an emergency disembarkation in Buenos Aires and intensive care treatment, the patient died within 72 hours of hospitalisation.
At this point, ship management alerted WHO and flag-state authorities. RT-PCR testing confirmed Andes virus in multiple passengers who had since developed milder symptoms.
WHO Formally Notified — May 2, 2026
Argentina notified WHO under International Health Regulations (IHR) on May 2. WHO published a Disease Outbreak News bulletin (DON-599) confirming three deaths and multiple additional cases. The bulletin flagged Andes virus as the only known hantavirus strain with documented person-to-person transmission potential, triggering heightened international concern.
Contact tracing began across 12 initial countries whose nationals were aboard the vessel.
Cape Verde Refuses Docking — May 5, 2026
With the ship still at sea, the captain sought permission to dock in Praia, Cape Verde, to facilitate medical evacuations. Cape Verde’s health ministry refused entry on public health grounds, citing insufficient biosafety infrastructure to manage a potential hantavirus cluster.
MV Hondius anchored in international waters off Praia while diplomatic negotiations continued.
Andes Strain Confirmed; Spain Approves Tenerife — May 6, 2026
Genomic sequencing of samples from the deceased passengers confirmed the pathogen as Andes virus (ANDV), native to South America and associated with rodent reservoirs in Andean and Patagonian regions. The sequencing results were shared with WHO and all affected country health authorities.
Spain’s health ministry, after consultation with ECDC, authorised MV Hondius to dock at Santa Cruz de Tenerife in the Canary Islands, with the condition that all passengers remain under observation and no disembarkation would occur until health authorities boarded.
CDC Escalates; UK UKHSA Activates — May 7, 2026
The US Centers for Disease Control and Prevention (CDC) issued a Level 3 Travel Health Notice — its highest advisory — specifically for persons who had travelled aboard MV Hondius. This was the first CDC Level 3 notice for a hantavirus event.
The UK Health Security Agency (UKHSA) activated its national health response protocol, establishing a dedicated Hondius incident management team and contacting all identified UK nationals from the manifest.
Six more countries — Ireland, Belgium, Australia, New Zealand, Austria and Italy — initiated formal contact-tracing programmes, bringing the total to 16 countries.
Arrival in Tenerife; WHO Confirms 6 Cases — May 8, 2026
MV Hondius arrived at Santa Cruz de Tenerife under Spanish public health supervision. WHO updated its case count to six confirmed infections. Disembarkation was permitted in stages under medical monitoring.
A US CDC charter flight was arranged for American passengers and their immediate family members, with CDC health officers travelling with the group.
Full Disembarkation; Vessel Under Quarantine — May 10, 2026
All passengers and non-essential crew disembarked by May 10. MV Hondius was placed under a mandatory decontamination protocol supervised by Spanish public health authorities. Separately, Argentine health authorities confirmed a seventh case — a crew member who had disembarked in Buenos Aires before the outbreak declaration.
WHO convened an emergency expert meeting on Andes virus person-to-person transmission, the first such consultation in the organisation’s history.
WHO Preliminary Findings; 8th Case in Canada — May 11, 2026
WHO’s expert panel released preliminary findings noting “limited but not conclusive” evidence of Andes virus person-to-person transmission based on the epidemiological data from the Hondius cluster. Full genome sequencing was expected within 72 hours to clarify transmission chains.
Health Canada simultaneously confirmed the first Canadian case — a British Columbia resident who had been a passenger on the voyage. ECDC upgraded its EU/EEA risk level from low-moderate to moderate. The total confirmed case count rose to eight, with three deaths.
What Remains Unknown
As of this writing, several critical questions remain unresolved:
- Transmission route: Were cases acquired from a shared rodent exposure during Antarctic landings, or did person-to-person transmission occur during the voyage?
- Index source: No rodent exposure event has been identified as the likely index exposure.
- Long-term outcomes: Three of the eight confirmed patients remain hospitalised.
- Vessel safety: When, if ever, MV Hondius will receive biosafety clearance for return to service.
For live updates, visit the HantavirusMap outbreak tracker and latest news page.
Sources
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