Key facts
- An Andes virus outbreak hit the Dutch expedition cruise ship MV Hondius in April and May 2026.
- 12 people tested positive. A 13th, the first patient, died before he could be tested. 3 people died.
- Passengers came from 23 countries, so cases and contacts were followed up worldwide.
- WHO declared the outbreak over on 2 July 2026, once the last close contact finished quarantine.
What happened
The ship left Ushuaia, Argentina, on 1 April 2026 with 114 passengers and 61 crew, bound for Antarctica and remote South Atlantic islands. The first patient, a Dutch man, fell ill on 6 April and died on board on 11 April. His death was first put down to natural causes.
Because nobody suspected hantavirus at first, 30 passengers left the ship at Saint Helena on 24 April and flew home before contact tracing began. The man's widow, who had also caught the virus, died in Johannesburg two days later. A German passenger died on board on 2 May.
The first positive test came on 4 May. Over the next weeks, cases were confirmed in South Africa, the Netherlands, Switzerland, the UK, France, Spain, Canada and on Tristan da Cunha.
Timeline
| Date (2026) | Event |
|---|---|
| 1 April | MV Hondius leaves Ushuaia, Argentina |
| 6 April | First passenger falls ill |
| 11 April | First death on board, not yet linked to hantavirus |
| 24 April | 30 passengers disembark at Saint Helena |
| 26 April | Second death, in Johannesburg |
| 2 May | Third death, on board. WHO receives first report |
| 3 May | Ship reaches Praia, Cape Verde. No one disembarks |
| 4 May | First positive test for Andes virus |
| 6 May | Three patients flown to the Netherlands. Ship sails for Tenerife |
| 10 to 11 May | Passengers disembark in Tenerife and are flown home for quarantine |
| 18 May | Ship reaches Rotterdam. Remaining crew quarantined, ship disinfected |
| 30 May | Dutch health authority clears the ship to sail again |
| 12 June | 21 countries launch a joint Andes virus research initiative |
| 2 July | WHO declares the outbreak over |
Where did the virus come from?
Andes virus normally lives in rodents in Argentina and Chile. The first patient and his wife had spent four months travelling through Chile, Uruguay and Argentina before boarding. Argentine scientists trapped rodents near Ushuaia and along the couple's route. They found a previously unknown hantavirus variant near Ushuaia, but it was not the one that spread on the ship. The exact source has not been confirmed.
What was learned
- The virus spread between people on board. It showed again that Andes virus can pass between people living in close quarters.
- Early cases look like flu. The first death was not recognised as hantavirus, which let passengers scatter before anyone was traced.
- Ships are poorly equipped for this. The infirmary had no ventilator or scanner for serious lung illness.
- Hospital protocols matter. Twelve staff at a Dutch hospital were isolated after not following strict precautions. None became ill.
- No new variant emerged. Sequencing of patient samples found no sign of a more dangerous or more transmissible strain.
Sources: WHO fact sheet and outbreak news, ECDC: Andes hantavirus outbreak in cruise ship, MV Hondius hantavirus outbreak (Wikipedia, with full citations)
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