Situation at a glance
On May 2, 2026, a group of travelers on a cruise ship reported serious respiratory issues to the World Health Organization (WHO). The ship, carrying 147 people in total, has since identified seven cases of severe illness by May 4, which include two confirmed hantavirus cases and five that are suspected. Tragically, three individuals have died, and one is critically ill, while three others show mild symptoms. Symptoms began between April 6 and April 28, presenting as fever and gastrointestinal distress, quickly escalating to pneumonia and respiratory distress. Investigations are still ongoing, and the situation is being handled with a coordinated international effort that involves case isolation, medical evacuations, and laboratory testing.
Hantavirus is usually spread through contact with the saliva, urine, or feces of infected rodents. It can be quite severe, and while human-to-human transmission isn’t common, it has been observed in past Andes virus outbreaks. For now, WHO assesses the overall risk to the global population as low and will continue to keep an eye on developments, updating risk evaluations as necessary.
Description of the situation
On May 2, 2026, the WHO was alerted by the United Kingdom’s National International Health Regulations (IHR) Focal Point about a cluster of acute respiratory illnesses on board a Dutch-flagged cruise ship. At that time, two deaths and one passenger in critical condition were reported. Laboratory tests from South Africa later confirmed hantavirus in one of the critically ill individuals. By May 3, another death had been tallied, and three more suspected cases were still on the ship. So, by May 4, the total stood at seven cases overall: two confirmed and five suspected, with three fatalities.
The ship set sail from Ushuaia, Argentina, on April 1, 2026, and traveled through several remote regions in the South Atlantic, stopping at locations like Antarctica, South Georgia, and Ascension Island. It’s unclear how much interaction passengers had with local wildlife during their journey or prior to boarding. The ship has 147 individuals on board, including 88 passengers and 59 crew members representing 23 different nationalities. As of May 4, it is currently anchored near Cabo Verde.
Summary of cases:
Case 1: An adult male exhibited symptoms like fever and mild diarrhea starting April 6 while aboard. He developed respiratory distress and died on April 11, without any microbiological tests carried out. His body was transported to Saint Helena on April 24.
Case 2: A close contact of Case 1, an adult female, went ashore on April 24 with gastrointestinal symptoms but deteriorated during a flight to Johannesburg on April 25 and died on April 26. On May 4, her hantavirus infection was confirmed via PCR.
Cases 1 and 2 had spent time in South America, including Argentina, before embarking on the cruise on April 1.
Case 3: An adult male reported to the ship’s physician on April 24 with febrile illness and shortness of breath, worsening his condition over the next days. He was evacuated to South Africa on April 27, where he remains in the ICU. Tests showed hantavirus infection on May 2, while other respiratory tests returned negative.
Case 4: An adult female showing pneumonia symptoms passed away on May 2; her symptoms began on April 28.
The three remaining suspected cases are reporting high fever and gastrointestinal symptoms and are still on board. Medical teams in Cabo Verde are assessing patients and collecting more samples for testing.
Public health response
A coordinated response has been initiated by authorities from Cabo Verde, the Netherlands, Spain, South Africa, and the United Kingdom. However, some key measures include:
- Regular communication between WHO and various national IHR Focal Points to ensure timely information sharing and coordinated actions.
- WHO informing global National IHR Focal Points about ongoing events.
- Passengers have been advised to maintain physical distancing and stay in their cabins as much as possible.
- Ongoing investigations to identify the source of exposure.
- Passenger and crew lists have been shared among relevant National IHR Focal Points based on nationality.
- Clinical management and evacuation support for symptomatic passengers have been initiated through formal discussions among emergency responders.
- Logistical support for sample collection is being provided.
- Hantavirus infections are being confirmed at South Africa’s National Institute for Communicable Diseases, with ongoing serology and genomic studies.
- Additional samples from symptomatic passengers are en route for testing in Senegal.
- WHO is implementing multi-level coordination to assist national authorities in enacting evidence-based public health measures as outlined in IHR guidelines.
WHO risk assessment
Hantavirus cardiopulmonary syndrome (HCPS), or hantavirus pulmonary syndrome (HPS), is a viral respiratory disease caused by hantaviruses. There are over 20 identified viral species in this family. In North America, Sin Nombre virus is the main cause of HPS, while Orthohantavirus andesense is prevalent in South America.
Hantavirus infections usually result from contact with rodent droppings, urine, or saliva. They can happen during tasks such as cleaning infested buildings or even in outdoor activities in areas with high rodent populations. Symptoms typically start 2-4 weeks post-exposure, but can appear sooner or later. While hantavirus infections aren’t common, reports show several cases in the Americas in recent years, with a case fatality rate of about 25.7% in 2025. European infection rates are currently low compared to previous years.
Although rare, human-to-human transmission of HPS via Andes virus has been observed in community situations involving extended contact. Documented cases among healthcare workers, while limited, have occurred.
At present, WHO considers the global risk from this incident to be low while continuing to monitor the epidemiological situation and will adjust risk evaluations as needed.
WHO advice
WHO recommends that involved states focus on detection, investigation, reporting, case management, and infection control while maintaining ship sanitation measures in close cooperation with the cruise operator.
Given the ongoing outbreak, passengers and crew are advised to wash hands often, be aware of hantavirus symptoms, and monitor their health for 45 days. Crews should ensure effective cleaning and ventilation aboard, and anyone feeling unwell should report it and self-isolate. Masks should be worn when experiencing respiratory issues.
Awareness is key, especially for those returning from areas with known hantavirus presence or engaged in eco-tourism.
Prompt identification of suspected cases and proper infection control practices are crucial in protecting healthcare workers.
Diagnosis of HPS involves testing for specific antibodies or viral RNA. Standard precautions should apply to all patients, with additional measures for those confirmed or suspected of having hantavirus.
Patients displaying symptoms should be moved to an emergency room or ICU for monitoring, with supportive care initiated as necessary. Standard treatments do not include antibiotics unless secondary infections are suspected.
Preventive measures should be set to minimize exposure, especially in occupational and eco-tourism settings. Public education should help avoid contact with rodents and unsafe cleaning methods.
Risk communication must be timely and culturally relevant to effectively convey hantavirus risks and promote preventive behaviors.
Lastly, surveillance for hantavirus should be a part of a larger national monitoring approach integrating clinical, laboratory, and environmental data.
