Andes Hantavirus Outbreak on the MV Hondius

A Multi-Country Crisis in the South Atlantic

A rare rodent-borne illness capable of limited person-to-person transmission struck an expedition cruise ship in April and May 2026, resulting in three deaths and at least 13 confirmed or probable cases among passengers and crew.

The outbreak, first reported to the World Health Organization on May 2, triggered a complex international response involving the evacuation and repatriation of passengers from over 20 countries, extensive contact tracing, and the implementation of quarantine measures. The ship's voyage began in Argentina and traversed the South Atlantic before the crisis unfolded.

Outbreak Origin and Initial Cases

April 1, 2026: The MV Hondius, a Dutch-flagged polar expedition cruise ship operated by Oceanwide Expeditions, departed from Ushuaia, Argentina. The ship carried 88 passengers and 61 crew members.

April 6, 2026: A 70-year-old Dutch male passenger developed symptoms including fever, headache, and mild diarrhea. He died five days later on April 11 after experiencing respiratory distress. No microbiological tests were performed at that time.

April 24, 2026: The body of the deceased passenger was disembarked at Saint Helena. His 69-year-old wife, who had been accompanying the body, developed gastrointestinal symptoms.

April 26, 2026: The Dutch woman collapsed at Johannesburg's O.R. Tambo International Airport and was taken to a hospital, where she died. Samples taken from her were subsequently sent for testing.

April 27, 2026: A British passenger who fell ill between Saint Helena and Ascension Island was medically evacuated to South Africa, where he was admitted to an intensive care unit.

First Deaths and Initial Response

April 11, 2026: The first passenger, a 70-year-old Dutch man, died on the ship. The ship's captain reportedly announced the death as resulting from "natural causes" and stated the deceased was "not infectious" per a doctor's assessment. No immediate public health precautions were implemented on board at that time.

April 24, 2026: The body of the deceased Dutch man and his wife were disembarked at Saint Helena. Approximately 29 to 40 passengers from at least 12 countries also disembarked at Saint Helena before the outbreak was identified. No contact tracing was conducted at this time.

April 26, 2026: The Dutch woman died in Johannesburg, South Africa. She had been on KLM flight KL-592 from Johannesburg to Amsterdam on April 25 but was removed from the aircraft before takeoff due to her medical condition.

Confirmation of Hantavirus

May 1-2, 2026: South African infectious disease specialists at the National Institute for Communicable Diseases (NICD) received an urgent request to investigate a passenger evacuated to a Johannesburg hospital with suspected pneumonia. After ruling out other pathogens, tests confirmed the presence of hantavirus. The strain was identified as the Andes virus. A Swiss passenger who had disembarked earlier also tested positive for the virus in Zurich.

May 2, 2026: A German woman who had been aboard the ship died. The World Health Organization (WHO) was formally notified of a cluster of severe respiratory illness.

May 3, 2026: The ship, with 149 people on board representing 23 nationalities, was anchored off the coast of Praia, Cape Verde. Cape Verdean health authorities denied the ship permission to dock due to public health concerns.

Virus Characteristics

The outbreak was caused by the Andes virus (ANDV) , a New World hantavirus endemic to South America. It is the only hantavirus strain with documented human-to-human transmission.

The working hypothesis is that the initial case acquired the infection on land in Argentina or Chile before boarding, through contact with infected rodent excreta. Subsequent cases on the ship are believed to have resulted from human-to-human transmission in the ship's close quarters.

International Response and Evacuation Plan

May 2-5, 2026: The WHO assessed the global risk as low. The WHO coordinated a multi-country response under the International Health Regulations, involving Cape Verde, the Netherlands, Spain, South Africa, the United Kingdom, and the United States. Measures included epidemiological investigations, isolation of cases, laboratory testing, and virus sequencing.

May 4, 2026: The WHO confirmed that human-to-human transmission could not be ruled out.

May 6, 2026: Three critically ill individuals (two crew members and a companion) were medically evacuated from the ship to the Netherlands.

May 7, 2026: The ship departed Cape Verde and began sailing toward the Canary Islands, Spain.

May 9, 2026: Spanish authorities, overruling a decision by Canary Islands President Fernando Clavijo, agreed to allow the ship to anchor off Tenerife for passenger evacuation.

Disembarkation and Repatriation at Tenerife

Arrival and Quarantine Procedures

May 10, 2026: The MV Hondius arrived at the port of Granadilla in Tenerife, Canary Islands. Passengers began disembarking in small boats. A 1.6-kilometer security zone was enforced around the ship. Passengers wore protective gear (PPE, face masks). They were taken by sealed, guarded buses to Tenerife Airport and transferred to repatriation flights. Luggage and the body of the deceased German passenger remained on the ship.

Repatriation by Country

• Australia: Four Australian citizens, one permanent resident, and one New Zealand citizen were repatriated via the Netherlands. They arrived at RAAF Base Pearce in Perth on May 15 and were transferred to the Centre for National Resilience in Bullsbrook for a minimum 21-day quarantine (subsequently extended to 42 days).

• France: Five French nationals were flown to Paris. One passenger tested positive for hantavirus and was hospitalized in critical condition, requiring ECMO (extracorporeal membrane oxygenation). All French passengers were placed in hospital isolation.

• Netherlands: Passengers were evacuated to the Netherlands and placed in quarantine.

• Spain: Fourteen Spanish passengers were quarantined at the Gómez Ulla Military Hospital in Madrid.

• United Kingdom: Twenty British nationals were flown to Arrowe Park Hospital in Merseyside for 72 hours of medical observation, followed by home isolation.

• United States: Seventeen American citizens and one British dual-national were evacuated to the National Quarantine Unit (NQU) at the University of Nebraska Medical Center. Upon arrival, one patient tested mildly positive for the Andes virus but remained asymptomatic. Two passengers were later transferred to Emory University Hospital in Atlanta for monitoring.

May 11, 2026: The evacuation was completed. The MV Hondius departed Tenerife with 25 crew members and two medical personnel on board, sailing for Rotterdam, Netherlands.

Confirmed Cases and Deaths

Fatalities

1. 70-year-old Dutch man: Died on the ship on April 11.
2. 69-year-old Dutch woman: Died in Johannesburg, South Africa, on April 26. Posthumously tested positive for Andes virus.
3. German national: Died on the ship on May 2. Cause of death was under investigation.

Confirmed Cases (Non-Fatal)

• British passenger: Evacuated to South Africa, hospitalized in intensive care.
• British passenger: Evacuated to the Netherlands, hospitalized.
• Dutch passenger: Evacuated to the Netherlands.
• Swiss passenger: Hospitalized in Zurich after disembarking earlier.
• French passenger: Hospitalized in critical condition in Paris.
• Spanish passenger: Quarantined and treated at a military hospital in Madrid.

Additional Countries with Confirmed or Suspected Cases

• Canada: One Canadian passenger tested presumptively positive in British Columbia.
• Switzerland: One passenger hospitalized in Zurich.
• Tristan da Cunha: A third British national was a suspected case.

Contact Tracing and Monitoring

Health authorities in at least ten U.S. states (Arizona, California, Georgia, Kansas, Maryland, Minnesota, New Jersey, Texas, Virginia, Washington) and several other countries monitored individuals who had potential exposure. This included passengers who disembarked at Saint Helena and people who shared flights with infected individuals.

• Saint Helena: Approximately 40 passengers who disembarked before the outbreak was known were tracked.
• South Africa: Contact tracing was conducted for passengers on a flight from Saint Helena to Johannesburg that carried the deceased Dutch woman.
• Netherlands: A KLM flight attendant who had brief contact with the infected Dutch woman tested negative for hantavirus. Twelve hospital staff were placed in precautionary quarantine after improper handling of a patient's samples.
• Spain: A woman in Alicante who shared a flight with a confirmed patient was tested and found to be negative.
• Singapore: Two residents tested negative.

Secondary Incidents

Tristan da Cunha

British paratroopers were deployed to the remote island of Tristan da Cunha to provide medical assistance to a patient with a suspected hantavirus case. The patient had been a passenger on the MV Hondius.

Independent Hantavirus Cases

Unrelated cases of hantavirus were reported in other regions during the same period, including a suspected case at a high school in Ontario County, New York, and a fatal case in Douglas County, Colorado. These were not connected to the cruise ship outbreak.

Sequencing and Research

The Pasteur Institute in France performed full genomic sequencing of the Andes virus from the infected French passenger. The analysis found that the virus sequences were:

• Identical to each other among shipboard cases.
• Approximately 97% similar to known Andes virus samples circulating in South America, including those found in rodents.

Health authorities stated that the genetic analysis showed no evidence of increased transmissibility, virulence, or mutation that would affect the virus's characteristics.

Ship Disinfection and Return to Service

May 18, 2026: The MV Hondius docked at the Port of Rotterdam, Netherlands, with the remaining 25 crew and two medical personnel. No one on board was symptomatic. The crew entered quarantine, and the ship underwent a three-day disinfection and cleaning process in accordance with Dutch public health guidelines.

Late May 2026: After cleaning and disinfection, and following inspections by local health authorities, the MV Hondius was cleared to return to service. All scheduled voyages from June 13, 2026, proceeded as planned.

End of Outbreak Monitoring

June 8, 2026: The government of Saint Helena declared the conclusion of the hantavirus incident, with no active or suspected cases remaining on the island after all contacts completed their 42-day mandatory isolation.

June 21, 2026: The 42-day monitoring period for the last U.S. passengers ended. The U.S. Centers for Disease Control and Prevention (CDC) ended its response to the outbreak, confirming no sustained transmission had occurred in the United States. The last eight American passengers were released from the National Quarantine Unit in Omaha, Nebraska.

June 23, 2026: The six passengers quarantined in Australia were released from the Bullsbrook facility. All had tested negative and remained asymptomatic.

Late June 2026: The WHO reported a total of 13 confirmed or probable cases linked to the ship, with no new deaths since May 2. The situation was described as stable.