Three people have died following a hantavirus outbreak on the Dutch expedition cruise ship MV Hondius, which left Ushuaia, Argentina, on April 2, 2026, with 147 passengers and crew on board. The World Health Organization confirmed on May 4 that the outbreak includes two laboratory-confirmed hantavirus cases and five suspected infections, with additional passengers showing either mild symptoms or severe illness. One patient is critically ill, and three deaths have been reported so far.
The outbreak began after several passengers developed a rapidly progressing respiratory illness while the ship was crossing the Atlantic. As the situation escalated, concern grew due to the confined environment of the vessel and limited access to advanced medical care. One severely ill passenger has already been transferred to a hospital in South Africa, and evacuation efforts are underway for others showing symptoms.
Hantavirus infections can lead to serious conditions such as hantavirus pulmonary syndrome (HPS) or hemorrhagic fever with renal syndrome (HFRS), both of which can be life-threatening. The virus is most commonly associated with exposure to infected rodents or their droppings, urine, or saliva. In some cases, particles can become airborne, increasing the risk of infection even without direct contact, which is especially concerning in enclosed environments like cruise ships.
Global health experts have warned that more cases could still emerge due to the virus’s incubation period, which can last up to a week. Larry Gostin, a public health law expert, said the situation is “very dangerous,” noting that it remains unclear what preventive measures were in place on the vessel. He emphasized that hantavirus is not easily transmitted between people, but environmental exposure can still lead to infection in outbreaks like this.
Experts also stressed that both major forms of the disease are “extraordinarily serious,” and treatment options are limited. There is no specific antiviral cure, so care typically relies on intensive hospital treatment, particularly when patients experience severe respiratory distress. Around 38% of severe hantavirus pulmonary syndrome cases can be fatal, underscoring the seriousness of the outbreak currently being monitored at sea.
Passengers and observers have described growing anxiety on board as uncertainty continues. Social media posts from those aboard reflect concern about safety and evacuation delays, while health officials continue tracking new symptoms as the ship remains in transit. With the incubation period not yet fully passed, authorities say the situation is still evolving and further cases remain possible.