At a glance (as of 13 August 2026)
- • Status: WHO formally closed the event on 22 July 2026 after 60 days with zero linked cases worldwide.
- • Ship: MV Hondius, Dutch-flagged expedition vessel, 147 people from 23 countries aboard at departure.
- • Pathogen: Andes virus (sequenced 11 May; no mutations of concern).
- • Final count: 12 confirmed cases, 3 deaths among passengers/crew. No onward spread after repatriation.
- • U.S. impact: No domestically acquired cases. Nebraska Quarantine Unit cohort released symptom-free on 21 June.
- • Travel notice: CDC downgraded Patagonia notice from Level 2 to Level 1 on 15 July.
- • Now: PAHO reports Southern Cone activity at seasonal baseline as of 12 August; new Patagonia cases are routine community exposures, not Hondius-linked.
Situation summary
On 2 May 2026, the Netherlands National Focal Point notified Argentina and the World Health Organization of two deaths and one critically ill passenger aboard the Dutch-flagged expedition cruise ship MV Hondius. The ship had departed Ushuaia, Tierra del Fuego on 1 April 2026 with 147 passengers and crew from 23 countries, on a South Atlantic itinerary covering South Georgia, the South Sandwich Islands and Saint Helena. Within days, sequencing at Argentina's ANLIS-Malbrán Institute confirmed the pathogen as Andes virus, the only hantavirus with documented person-to-person transmission. The ship is currently docked off Cape Verde, which is leading the at-sea public-health response in coordination with WHO, PAHO, CDC, ECDC and the Netherlands.
Event timeline
Case counts (as of 22 July 2026 — final)
| Setting | Confirmed | Suspected | Deaths |
|---|---|---|---|
| Aboard MV Hondius (multi-national) | 12 | 0 | 3 |
| Disembarked passengers under monitoring | 0 | 0 | 0 |
| Argentina (community, 2026 YTD) | 68 | 21 | 14 |
| Chile (community, 2026 YTD) | 22 | 7 | 4 |
| United States (acquired domestically) | 0 | 0 | 0 |
Compiled from the WHO closure notice (22 July 2026), CDC situation summary and Level 1 travel notice update (15 July 2026), PAHO Patagonia surveillance summary, and Argentina Ministry of Health bulletins. See our live news feed for any post-closure updates.
The MV Hondius incident in detail
The MV Hondius is a 108-passenger expedition ship operated by Oceanwide Expeditions, regularly sailing Antarctic and sub-Antarctic itineraries. Investigators believe the index case is a Dutch couple who spent roughly 100 days driving through Patagonia, Chile, Mendoza, Misiones and Uruguay before re-entering Argentina on 27 March 2026 and boarding in Ushuaia on 1 April. The first severe case (Patient 3) was medically evacuated to Ascension Island on 27 April with severe acute respiratory infection and later transferred to Johannesburg, where he died. Whether transmission first occurred on shore in Patagonia or via shipboard rodent activity remains under investigation; Argentine teams from the Malbrán Institute are trapping rodents in Ushuaia to characterize the local virus reservoir.
U.S. response and the Nebraska Quarantine Unit
On 10 May 2026, the CDC — in coordination with the U.S. State Department, Department of Defense and Nebraska public health authorities — repatriated 18 U.S. passengers still aboard the ship. They are housed at the National Quarantine Unit at the University of Nebraska Medical Center for a 42-day monitoring period (well beyond the virus's typical 6-week incubation window). Seven U.S. passengers who disembarked earlier are being monitored at home by state and local health departments. The CDC has issued two Health Alert Network advisories:
- HAN 00528 — alerts clinicians to the multi-country cluster and imported-case considerations.
- HAN 00529 — outlines testing pathways for suspected Andes virus infection, including specimen submission to CDC.
International response
- Argentina (Ministerio de Salud, ANLIS-Malbrán): Sequenced the virus, dispatched Andes virus RNA and ELISA plates (~2,500 diagnostic tests' worth) to Spain, Senegal, South Africa, the Netherlands and the United Kingdom; running rodent capture studies in Tierra del Fuego.
- Cape Verde: Leads on-vessel public health management while the ship is in its waters.
- Netherlands & Dutch operator: Initial notifying state; coordinating repatriation logistics for non-U.S. passengers.
- Spain (22 May): Permits contacts with two consecutive negative PCRs to complete the final 14 days of monitoring at home rather than in hospital.
- WHO / PAHO / ECDC: Joint Disease Outbreak News and risk assessments published; risk to the general public outside the cluster assessed as low.
- CDC: Daily clinical briefings; situation summary updated 19 May; risk to the U.S. public assessed as "extremely low."
If you were on board or in close contact with a passenger
- Follow direct guidance from the public-health authority in the country where you disembarked. Monitoring is typically 42 days from last exposure.
- Watch for fever, severe muscle aches (especially thighs and back), headache, gastrointestinal symptoms and — critically — any new shortness of breath.
- If symptoms appear, seek emergency care immediately and tell the clinician you may have been exposed to Andes hantavirus. Early ICU-level supportive care, including ECMO, dramatically improves outcomes.
- See our symptoms and diagnosis & treatment pages.
Why Andes virus outbreaks demand extra caution
Unlike Sin Nombre virus or the Old World hantaviruses, Andes virus has well-documented person-to-person transmission, especially in close household, healthcare and shipboard settings. The 2026 cluster is consistent with that pattern: prolonged shared air space and close contact aboard a small expedition vessel. Read our Andes virus background and transmission pages for the underlying biology.
Primary sources
- CDC — Andes Virus Outbreak on a Cruise Ship: Current Situation (19 May 2026), cdc.gov/hantavirus/situation-summary/
- CDC Health Alert Network 00528 and 00529 (May 2026).
- WHO Disease Outbreak News — Hantavirus disease (Andes virus) — multi-country (May 2026).
- Argentina Ministerio de Salud / ANLIS-Malbrán bulletins, May 2026.
- EL PAÍS English — initial genetic analysis confirms Andes strain (11 May 2026).
- NEJM Evidence — Andes Hantavirus Outbreak on a Cruise Ship, 2026 (CIDRAP mirror).
- Congressional Research Service — Current Hantavirus Outbreak (18 May 2026).