Timeline
On 22 April 2026 the MV Hondius departed Buenos Aires for Tenerife with passengers from seven nationalities. By 24 April the index passenger — a 64-year-old Argentinian man from Bariloche, Río Negro — was symptomatic on board. Three crew members and two close-contact passengers developed symptoms over the following ten days. Three patients died; the others were evacuated to hospitals in Tenerife and aboard a Spanish naval medical vessel. WHO published DON 2026-DON599 on 4 May and DON 2026-DON600 on 8 May.
Why this was a person-to-person Andes-virus event
Andes virus is the only hantavirus species with documented human-to-human transmission, with prior family-cluster events totalling roughly 12% of confirmed cases. The MV Hondius cluster fits the pattern: an enclosed environment, prolonged close contact with a heavily-shedding index case, and confirmed Andes-virus genome sequencing across multiple patients matching the index strain.
Public health response
PAHO co-ordinated contact tracing across the seven nationalities represented on the manifest. Spain, Cape Verde, the United Kingdom and Argentina activated their IHR focal points. No tertiary cases (contacts of contacts) were identified, suggesting the chain ended on the ship.
Significance
The event ended the post-2005 lull in major Andes-virus person-to-person events and prompted European public-health agencies to add hantavirus to their imported-disease surveillance protocols. It also accelerated CEPI funding for Andes-virus mRNA vaccine development.