Hantavirus is a rare infectious disease that spreads through contact with rodents and which can lead to kidney failure and fluid filling the lungs

By Adam Kovac edited by Claire Cameron

A suspected outbreak of hantavirus, a rare and deadly infectious disease, on a cruise ship currently off West Africa has killed three people and sickened at least three more.

The first fatality—a Dutch man—occurred on April 11, although no cause of death could be determined at the time. His wife later fell ill and also died, while a German national died on the ship on May 2; a further three people are believed to have been infected with hantavirus, including one who is in intensive care in South Africa. One case of the infection has been confirmed in a laboratory, according to the World Health Organization (WHO).

The cruise ship at the center of the outbreak is MV Hondius, operated by Oceanwide Expeditions; some 150 passengers remain on board. As of Monday morning, Oceanwide said in a statement that not all of the infections have been confirmed to be hantavirus, and that local health authorities had visited the ship but they have not yet approved the disembarkation of passengers or medical evacuation of two crew members who have fallen ill.

On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.

"Preparations are being made for possible medical repatriation and next steps," the company said in the statement. “Oceanwide Expeditions is in close contact with those directly involved and their families, and is providing support where possible.” The company did not immediately respond to a request for further comment.

What is hantavirus?

Hantaviruses are primarily spread through contact with rodents like rats and mice, and particularly through exposure to their urine, droppings and saliva, according to the U.S. Centers for Disease Control and Prevention (CDC). Generally, people breathe the virus in when particles of rodent feces or urine are disturbed. The infection may also spread from person-to-person, according to the CDC; it's unclear whether the ongoing outbreak is an example of that happening. The only variant of the virus known to have spread from one person to another is the Andes virus, which occurs in South America.

Infections typically map onto two syndromes—hantavirus pulmonary syndrome, and hemorrhagic fever with renal syndrome.

The mortality rate for hantavirus pulmonary syndrome is 38 percent. Symptoms usually start to present one to eight weeks after exposure to the pathogen and can include fatigue, fever and muscle aches, while about half of all infected people can also experience headaches, dizziness, chills, nausea, vomiting, diarrhea and abdominal pain. Within four to 10 days of the initial symptom onset, people typically start coughing and experiencing shortness of breath while the lungs fill with fluid. The disease was blamed for killing the actor Gene Hackman's wife in February, 2025.

Hemorrhagic fever with renal syndrome, meanwhile, has several different variants, with mortality rates varying from 1 percent to 15 percent. Symptoms can include intense headaches, back and abdominal pain, fever and chills, nausea and blurred vision. As the disease progresses, new symptoms can arise, including low blood pressure, lack of blood flow, internal bleeding and acute kidney failure.

Diagnosing the disease early in the course of an infection is hard, particularly due to the early symptoms’ similarities to influenza. And treatment is also difficult: there are no known cures, though the drug ribavirin has shown signs of reducing mortality, according to the WHO. Antivirals and other supportive interventions may help manage symptoms, but preventing an infection is key.

In the U.S., hantavirus is most commonly spread by the deer mouse and causes hantavirus pulmonary syndrome, according to the CDC. The agency recommends limiting contact with rodents at home or in any enclosed space to help reduce the risk of the disease, and wearing protective gear like an N95 mask and gloves if you have to clean up after any rodents.

Editor's note: This is a developing story and may be updated.