A rare outbreak of Hantavirus infection linked to a cruise ship has prompted international health monitoring, with the World Health Organization coordinating contact tracing across countries to contain any further spread.Swiss authorities confirmed that a passenger from the MV Hondius,  a luxury cruise ship, tested positive after reporting to a hospital in Zurich.Swiss authorities have confirmed a case of #hantavirus identified in a passenger from the MV Hondius cruise ship.He had responded to an email from the ship’s operator informing the passengers of the health event, and presented himself to a hospital in Zurich, Switzerland, and… pic.twitter.com/4mmBd7qSA4— World Health Organization (WHO) (@WHO) May 6, 2026The patient is receiving treatment. Health agencies in multiple countries, including South Africa and Argentina, are now tracking potential exposures following the outbreak.Officials said the strain involved is the Andes virus, a rare form of hantavirus found mainly in South America that can, in uncommon cases, spread between humans. According to health authorities, at least eight cases have been identified so far, with three laboratory-confirmed infections and multiple deaths reported among passengers.What is hantavirus?Hantavirus refers to a group of viruses primarily spread by infected rodents. Humans can contract the virus through exposure to rodent urine, droppings or saliva, especially in poorly ventilated spaces. The infection can lead to serious conditions such as Hantavirus Pulmonary Syndrome (HPS), which affects the lungs, or haemorrhagic fever impacting the kidneys.How does it spread?The virus is mainly transmitted when people inhale contaminated air particles from rodent waste. It can also spread through direct contact with infected rodents or, rarely via bites. Most hantavirus strains do not spread between humans. However, the Andes strain identified in this outbreak is known for limited person-to-person transmission, typically through close contact such as shared living spaces.Outbreak detailsThe cruise ship outbreak began after passengers who had travelled in Argentina boarded the vessel. Cases later emerged onboard, with infections confirmed after some passengers were evacuated to South Africa. One British passenger is currently in intensive care, while another case was confirmed posthumously.The ship is currently off the coast of Cape Verde, with additional passengers under observation. Authorities are working to evacuate those still onboard and prevent further spread.Symptoms and risksEarly symptoms include fever, fatigue, headaches and muscle pain, which can quickly escalate to coughing, shortness of breath and severe respiratory distress. In serious cases, fluid builds up in the lungs, making the condition life-threatening. There is no specific cure and treatment focuses on supportive care.Prevention and precautionsExperts advise maintaining hygiene and avoiding contact with rodents. Using protective gear while cleaning potentially contaminated areas and sealing entry points in homes can reduce risk. People exposed to rodents should seek medical attention if flu-like symptoms develop.The WHO said it will continue working with countries to monitor the situation, support affected patients and ensure that passengers and contacts receive timely guidance to limit the spread of the virus.