Hantavirus Updates: What’s Happening, How It Spreads, and What to Know

Last updated: May 18, 2026
Status: Living article — this page will be updated as new verified information becomes available.
Medical note: This article is for public information only and is not medical advice. If you may have been exposed to rodents, were aboard the MV Hondius, had close contact with someone under monitoring, or develop symptoms, contact a medical professional or your local public-health authority.

Latest update

Update — May 18, 2026: Public-health agencies are continuing to monitor a multi-country Andes hantavirus outbreak linked to the Dutch-flagged expedition cruise ship MV Hondius.

The European Centre for Disease Prevention and Control now lists 12 total reported cases connected to the outbreak: 9 confirmed, 2 probable, 0 suspected, and 1 inconclusive, with 3 deaths. ECDC says no new deaths have been reported since its previous update, and the risk to the EU/EEA general population remains very low. (ECDC)

The MV Hondius arrived in Rotterdam, Netherlands, on May 18 with 27 crew members on board after passengers had already disembarked and been repatriated. The ship is undergoing public-health handling, quarantine procedures, cleaning, and disinfection. (ECDC)

The outbreak virus has been identified as Andes virus, a type of hantavirus associated with parts of South America. Andes virus is unusual because it is the only hantavirus known to sometimes spread from person to person, generally through close or prolonged contact, not casual public exposure. CDC says no cases of Andes virus have been confirmed in the United States as a result of this outbreak, and that the risk of a pandemic from this outbreak and the overall risk to the American public and travelers is extremely low. (CDC)

The current public-health message remains cautious but not panic-driven: the outbreak is serious for exposed passengers, crew, and close contacts, but health agencies are not describing it as a broad public-health emergency for the general public.

Situation at a glance

ECDC says the ship originally involved passengers and crew from 23 countries, including nine EU/EEA countries. CDC says the ship carried 147 people, including 86 passengers and 61 crew, and traveled from Ushuaia, Argentina, across the South Atlantic, stopping at remote locations including Antarctica, South Georgia Island, Tristan da Cunha, Saint Helena, and Ascension Island. (ECDC)

What changed since the previous update

Earlier WHO updates reported 8 cases by May 8 and 11 cases by May 13. The May 13 WHO report listed 8 confirmed cases, 2 probable cases, 1 inconclusive case in the United States, and 3 deaths. WHO also said two additional confirmed cases had been reported from France and Spain since the May 8 update. (World Health Organization)

As of ECDC’s May 18 update, the total has increased to 12 reported cases, including 9 confirmed, 2 probable, and 1 inconclusive. ECDC specifically notes that Canada reported a cruise passenger who tested presumptively positive for Andes hantavirus on May 16; based on available information, ECDC classifies that case as confirmed. (ECDC)

The ship has now reached Rotterdam for disinfection and public-health handling. AP reported that the vessel arrived with 25 crew members and two medical personnel, that the crew would enter quarantine, and that the ship would be decontaminated under Dutch public-health guidance. (AP News)

Country-by-country outbreak status

This outbreak is multi-country because the ship carried passengers and crew from many countries, some people disembarked before the outbreak was fully recognized, and exposed travelers returned to multiple countries.

Important distinction: not every country listed below has confirmed infections. Some countries have confirmed cases; others have exposed passengers, contacts, repatriated travelers, or people under monitoring.

United States

The United States has no confirmed Andes virus cases from the MV Hondius outbreak, according to CDC. CDC’s current situation page says: “To date, no cases of Andes virus have been confirmed in the United States as a result of this outbreak.” CDC also says the risk of a pandemic caused by this outbreak and the overall risk to the American public and travelers is extremely low. (CDC)

CDC repatriated 18 passengers who remained on the ship on May 10. Those passengers were taken to the Nebraska Quarantine Unit at the University of Nebraska Medical Center for assessment and monitoring planning. CDC also says seven passengers who returned earlier are being monitored at home by state and local health officials. (CDC)

WHO’s May 13 report listed one inconclusive result in a case in the United States, with further testing underway at that time. This is not the same as a confirmed U.S. case. CDC’s latest public statement remains that no U.S. outbreak-linked Andes virus cases have been confirmed. (World Health Organization)

Separate from this cruise outbreak, hantavirus is already a rare but known illness in the United States, usually linked to rodent exposure. CDC reports that 890 laboratory-confirmed hantavirus disease cases were reported in the United States from the start of surveillance in 1993 through the end of 2023. PAHO also reported provisional U.S. hantavirus pulmonary syndrome data for 2025 through epidemiological week 47.

Canada

Canada now has a confirmed outbreak-linked case. ECDC says that on May 16, 2026, Canada reported that a cruise passenger tested presumptively positive for Andes hantavirus; the person was already under quarantine and had mild symptoms. ECDC classifies the case as confirmed based on the available information. (ECDC)

The Public Health Agency of Canada says the overall risk to the Canadian general population from the Andes hantavirus outbreak linked to the MV Hondius remains low, and that person-to-person spread in Canada is not expected because transmission requires close, prolonged contact. (Canada)

Netherlands

The Netherlands is central to the response because the MV Hondius is Dutch-flagged and has now returned to Rotterdam. ECDC says the ship arrived in Rotterdam on May 18 with 27 crew members on board. AP reported that the ship docked in Rotterdam for disinfection and that Dutch public-health officials arranged quarantine and testing for remaining crew. (ECDC)

AP also reported that three passengers have died, including a Dutch couple whom health officials believe were likely first exposed while visiting South America. The Netherlands has also been involved in hospital care, quarantine, ship handling, and disinfection procedures. (AP News)

Spain

Spain played a major operational role because passengers disembarked in Tenerife, Canary Islands, before onward repatriation. WHO’s May 13 update reported that one of the additional confirmed cases since May 8 was from Spain. (World Health Organization)

ECDC reported that after disembarkation and repatriation of passengers, the MV Hondius later arrived in Rotterdam. Spain’s role has included receiving the ship, coordinating disembarkation, supporting onward travel, and managing public-health procedures for exposed travelers. (ECDC)

France

France is linked through at least one confirmed case. WHO’s May 13 update reported one of the additional confirmed cases from France. (World Health Organization)

AP reported that a French cruise passenger remained in intensive care and that France’s Pasteur Institute fully sequenced the Andes virus detected in that French passenger. According to AP, the Pasteur Institute found the virus matched strains already known in South America, with no evidence so far of new characteristics that would make it more transmissible or more dangerous. (AP News)

Germany

Germany is linked through passengers and deaths reported in the outbreak. Earlier international reporting described one of the deaths as involving a German passenger. Some German nationals or residents have also been among exposed or monitored travelers.

Because official public-health agencies have not published a complete public country-by-country case table for every nationality, this page avoids assigning a precise final German case count beyond confirmed reporting that Germany is among the countries connected to the outbreak by passenger nationality and outcome.

United Kingdom

The United Kingdom was involved early in the international notification process. WHO says it received notification on May 2 from the United Kingdom’s National IHR Focal Point about a cluster of severe acute respiratory illness, including deaths and a critically ill passenger, aboard the Dutch-flagged cruise ship. (World Health Organization)

UK public-health authorities have also been involved in monitoring, isolation, and repatriation of British nationals and contacts. The UK’s role is especially important because the initial formal international notification came through UK IHR channels.

Switzerland

Switzerland has been linked through hospital care and testing of a passenger associated with the outbreak. Earlier WHO and international reporting described patients being treated in several countries, including Switzerland.

At this stage, country-level details are still being refined by public-health authorities, so this page avoids overstating a final Swiss total unless WHO, ECDC, or Swiss authorities publish a full country-by-country table.

South Africa

South Africa is linked to the early recognition and investigation of the outbreak because passengers traveled there after disembarking, and South African testing contributed to identifying the virus. WHO’s earlier updates described international contact tracing through IHR channels and the involvement of multiple national public-health authorities. (World Health Organization)

South Africa remains important in the timeline because some passengers traveled through or received care there before the outbreak was fully characterized.

Argentina

Argentina is central to the exposure investigation because the MV Hondius departed from Ushuaia, Argentina, on April 1, 2026, and Andes virus is associated with parts of South America. CDC says the ship departed Ushuaia and traveled through remote South Atlantic locations. (CDC)

Argentina also has ongoing endemic hantavirus activity. PAHO reported that Argentina had 66 confirmed hantavirus pulmonary syndrome cases between epidemiological week 1 and week 47 of 2025 and continued to report the highest number of cases in the Americas region.

Australia and New Zealand

Australia and New Zealand have been linked through repatriated travelers and monitoring of citizens or residents who were connected to the ship. These links do not necessarily mean confirmed infections.

Public-health handling for these travelers has focused on isolation, monitoring, testing, and coordination with international agencies because Andes virus has a long incubation period and can rarely spread between people through close contact.

Cabo Verde, Saint Helena, and Ascension Island

Cabo Verde, Saint Helena, and Ascension Island are important to the operational timeline because the ship’s route and medical evacuations involved remote Atlantic locations. CDC lists Saint Helena and Ascension Island among the ship’s stops and says the ship traveled across the South Atlantic after departing Argentina. (CDC)

These locations matter for exposure investigation, contact tracing, evacuation logistics, and onward passenger movement.

Other countries with passengers, crew, or contacts

The ship carried passengers and crew from 23 countries, according to ECDC and CDC. Not all of those countries have confirmed infections. Some may only have exposed passengers, contacts, crew members, or repatriated travelers under monitoring. (ECDC)

Until WHO, ECDC, or national health agencies publish a complete country-by-country case table, this page distinguishes between:

• Confirmed cases: laboratory-confirmed or officially classified by public-health agencies
• Probable cases: cases meeting public-health criteria but not fully confirmed
• Inconclusive cases: cases still undergoing further testing or classification
• Monitored contacts/travelers: people who may have been exposed but are not confirmed cases

Broader hantavirus activity outside the cruise outbreak

The MV Hondius outbreak is receiving global attention, but hantaviruses are not new. They circulate in different rodent populations in different parts of the world and can cause different clinical syndromes.

In the Americas, PAHO reported increased hantavirus pulmonary syndrome activity in 2025. Through epidemiological week 47 of 2025, eight countries in the Americas had reported cases: Argentina, Brazil, Bolivia, Chile, Panama, Paraguay, the United States, and Uruguay. Together, those countries reported 229 cases and 59 deaths, for a regional case-fatality rate of 25.7%.

PAHO noted that Bolivia and Paraguay reported significant increases compared with historical averages, while Argentina and Brazil saw increased lethality compared with recent averages. PAHO also emphasized the need to strengthen surveillance, timely diagnosis, case management, and environmental and occupational risk reduction.

Americas: 2025 PAHO regional context

The broader takeaway is that the cruise outbreak is unusual because of the ship setting and Andes virus classification, but hantavirus risk itself is usually tied to rodent exposure and is already monitored in several countries.

What is hantavirus?

Hantaviruses are a family of viruses carried mainly by rodents. People usually become infected when they are exposed to infected rodent urine, droppings, saliva, or nesting material. This can happen when contaminated particles become airborne and are inhaled, especially during unsafe cleaning of enclosed spaces with rodent contamination.

Hantaviruses can cause serious illness. In the Americas, they are associated with hantavirus pulmonary syndrome, a severe disease that affects the lungs. CDC says the Andes virus responsible for the MV Hondius outbreak can lead to hantavirus pulmonary syndrome, which is severe and potentially deadly. (CDC)

What is Andes virus?

Andes virus is a hantavirus associated with parts of South America. It is important because, unlike most hantaviruses, Andes virus can sometimes spread from person to person.

That does not mean it spreads like measles, COVID-19, or influenza. Public-health agencies describe Andes virus person-to-person spread as rare and typically associated with close, prolonged contact, especially with someone who is sick.

The MV Hondius outbreak is being taken seriously because of this person-to-person possibility, the severity of hantavirus pulmonary syndrome, and the long incubation period.

How hantavirus spreads

Most hantavirus infections are linked to rodents, not casual contact with people.

Higher-risk situations include:

• Cleaning cabins, sheds, barns, garages, storage rooms, attics, basements, or holiday homes where rodents may have nested
• Sweeping or vacuuming dry rodent droppings, which can stir contaminated particles into the air
• Camping, hiking, farming, forestry, field work, or spending time near rodent habitats
• Handling contaminated nesting material, food-storage areas, traps, or dead rodents without precautions
• Working in enclosed or poorly ventilated spaces where rodent droppings or urine are present

For Andes virus specifically, additional concern applies to close contact with an infected person. That can include close household-style contact, caregiving, direct exposure to bodily fluids, or prolonged time in close proximity during the infectious period.

Symptoms to watch for

Symptoms can resemble flu at first. Early symptoms may include:

• Fever
• Fatigue
• Muscle aches
• Headache
• Chills
• Dizziness
• Nausea
• Vomiting
• Diarrhea
• Abdominal pain

Later symptoms can include:

• Cough
• Shortness of breath
• Chest tightness
• Difficulty breathing
• Fluid buildup in the lungs
• Rapid worsening of respiratory illness

CDC describes hantavirus pulmonary syndrome as severe and potentially deadly. Anyone who develops flu-like symptoms after possible rodent exposure, after travel linked to the MV Hondius, or after close contact with a person being monitored for Andes virus should seek medical care promptly and mention the possible exposure. (CDC)

Incubation period and why monitoring continues

One reason public-health agencies are continuing to monitor exposed passengers and contacts is that Andes virus can have a long incubation period. ECDC says additional cases after former passengers and crew return home are expected given the long incubation period and the possibility that some infections occurred on board the ship. (ECDC)

This means a person can appear well at the time of repatriation or disembarkation but still require monitoring afterward.

How serious is it?

Hantavirus infections are rare, but they can be severe. WHO’s May 8 report listed 8 cases and 3 deaths, a case-fatality ratio of 38% at that point. WHO’s May 13 report listed 11 cases and 3 deaths, a case-fatality ratio of 27%. (World Health Organization)

ECDC’s May 18 update lists 12 reported cases and 3 deaths. (ECDC)

These ratios can change as more cases are found, reclassified, or ruled out. A small outbreak can also make percentages look unstable. The practical conclusion is still clear: hantavirus is uncommon, but when serious disease develops, it requires urgent medical attention.

Risk to the general public

Public-health agencies are not describing this as a broad public-health emergency for the general public.

• ECDC: risk to the EU/EEA general population remains very low. (ECDC)
• CDC: no outbreak-linked Andes virus cases have been confirmed in the United States; the risk of a pandemic from this outbreak and the overall risk to the American public and travelers is extremely low. (CDC)
• WHO: global population risk from the event has been assessed as low, while the risk for passengers and crew on the ship was considered higher because of their exposure setting. (World Health Organization)
• Canada: the overall risk to the Canadian general population remains low. (Canada)

The reason public-health agencies are still acting aggressively is not because the general public is at high risk. It is because exposed passengers, crew, and close contacts need monitoring, and because Andes virus is one of the rare hantaviruses that can spread person-to-person under close-contact conditions.

How to reduce risk

The best prevention is rodent control and safe cleanup.

Basic prevention steps:

• Seal holes and gaps where rodents can enter homes, cabins, garages, sheds, barns, or storage spaces.
• Store food, pet food, and trash in sealed containers.
• Avoid stirring up dust in areas with rodent droppings.
• Do not dry sweep or vacuum rodent droppings.
• Ventilate enclosed spaces before cleaning.
• Wet contaminated areas with disinfectant before cleanup.
• Wear gloves when handling contaminated materials.
• Follow public-health guidance for traps, dead rodents, and heavily contaminated spaces.
• Seek professional cleanup help for heavy infestations.

For Andes virus exposure risk:

• Avoid close personal contact with someone suspected or confirmed to have Andes virus unless following medical or public-health guidance.
• Avoid direct contact with body fluids from a sick person.
• Follow quarantine, isolation, testing, and monitoring instructions if identified as exposed.
• Tell clinicians about any relevant cruise, rodent, or close-contact exposure if symptoms develop.

What is still unknown

Several important questions remain under investigation:

• Where the initial exposure occurred
• Whether the first infections came from rodent exposure before boarding, during travel, during excursions, or on board
• Whether any person-to-person transmission occurred among passengers, crew, medical staff, or close contacts
• Whether additional cases will appear during the incubation period
• Whether all countries will classify cases the same way after retesting
• Whether genetic sequencing identifies any unusual features
• Whether ship route, port stops, wildlife exposure, passenger excursions, or pre-cruise travel explain the exposure pattern
• Whether environmental testing or ship inspection identifies a specific contamination source

AP reported that France’s Pasteur Institute sequenced Andes virus from a French passenger and found it matched viruses already known in South America, with no evidence so far of new traits that would make it more transmissible or more dangerous. (AP News)

Update log

May 18, 2026 — Updated ECDC count to 12 reported cases, including 9 confirmed, 2 probable, 0 suspected, 1 inconclusive, and 3 deaths. Added the Canadian confirmed case, Rotterdam arrival, ship disinfection status, and updated U.S. section confirming CDC still reports no confirmed U.S. Andes virus cases from this outbreak. (ECDC)

May 13, 2026 — WHO reported 11 cases, including 8 confirmed, 2 probable, 1 inconclusive, and 3 deaths. WHO reported two additional confirmed cases from France and Spain, and one inconclusive result in the United States. (World Health Organization)

May 8, 2026 — WHO reported 8 cases, including 6 confirmed, 2 probable, and 3 deaths. All six laboratory-confirmed cases were identified as Andes virus. WHO assessed the risk to the global population as low and the risk for passengers and crew on the ship as moderate. (World Health Organization)

May 2, 2026 — WHO was notified of a cluster of severe acute respiratory illness among passengers and crew aboard the MV Hondius. The cluster included deaths and a critically ill passenger, and testing later confirmed hantavirus. (CDC)

Sources being monitored

This page prioritizes information from:

• World Health Organization
• European Centre for Disease Prevention and Control
• U.S. Centers for Disease Control and Prevention
• Pan American Health Organization
• Public Health Agency of Canada
• UK Health Security Agency
• National health ministries and public-health agencies in affected countries
• Reputable international reporting, especially AP, when it cites named public-health officials, hospitals, public-health agencies, or ship operators

Bottom line

Hantavirus is rare, but it can be serious. The MV Hondius outbreak is unusual because it involves Andes virus, the one hantavirus known to rarely spread between people through close or prolonged contact.

For the general public, health agencies continue to describe the risk as low, very low, or extremely low. For exposed passengers, crew, and close contacts, the situation is more serious because of the incubation period, the severity of hantavirus pulmonary syndrome, and the need for monitoring.

For readers in the United States, the key point is that CDC reports no confirmed Andes virus cases in the United States from this outbreak. Some Americans are being monitored because they were exposed, but monitoring is not the same as infection. (CDC)

The practical takeaway is not panic — it is prevention: avoid rodent exposure, clean contaminated areas safely, follow public-health instructions if you were connected to the cruise, and seek medical care quickly if symptoms develop after possible exposure.