Three passengers aboard the polar cruise ship MV Hondius have died following a suspected outbreak of hantavirus, according to the World Health Organization (WHO). The vessel was traveling between Argentina and Cape Verde when the outbreak occurred. At least one case has been confirmed, with one patient in intensive care in a South African hospital. Two of the deceased were a couple from the Netherlands.
What is Hantavirus?
Orthohantaviruses, commonly known as hantaviruses, are a group of viruses primarily found in rodents but capable of infecting humans. According to Prof Adam Taylor of Lancaster University, there are at least 38 recognized species of hantavirus globally, 24 of which cause disease in humans. Rodents such as mice, rats, and voles serve as natural reservoirs for these viruses. Dr Yomani Sarathkumara, a postdoctoral research fellow at the University of Queensland, noted that hantavirus infections are “really rare in humans” and are often misdiagnosed in tropical countries as other infections like leptospirosis.
How is Hantavirus Spread and What are the Symptoms?
Hantaviruses are transmitted to humans through inhalation or contact with infected rodent faeces, urine, or saliva, and more rarely through bites or scratches. Agricultural communities are at higher risk due to increased likelihood of exposure. Associate Prof Vinod Balasubramaniam, a molecular virologist at Monash University Malaysia, emphasized that hantaviruses are “typically an environmental exposure linked to rodents” and “do not usually spread easily from person to person.”
There are two major lineages: old world hantaviruses (found in Europe and Asia) and new world hantaviruses (found in the Americas). Old world types, such as Puumala, Hantaan, and Seoul viruses, typically cause haemorrhagic fever with renal syndrome (HFRS), affecting the kidneys. Symptoms include intense headaches, back and abdominal pain, fever, and potential kidney damage. New world hantaviruses usually cause hantavirus pulmonary syndrome (HPS), with rapidly progressive respiratory failure. Early symptoms resemble flu, making diagnosis difficult. In March 2025, Betsy Arakawa, wife of actor Gene Hackman, died from HPS.
Incubation periods range from one to eight weeks. Human-to-human transmission is rare, with limited evidence for the Andes strain in South America.
How Did the Cruise Ship Outbreak Occur?
The WHO is investigating the outbreak. Possible causes include rodent contamination on the ship, exposure during land-based activities (given the long incubation period), or, less likely, person-to-person transmission. Balasubramaniam noted that the main risk is disturbing contaminated rodent materials in poorly ventilated spaces.
Mortality Rate and Treatment
Fatality rates for HFRS range from 1% to 15%, while HPS has a fatality rate of about 40% in the Americas. There is no definitive antiviral treatment; supportive care includes oxygen, fluid management, blood pressure support, and ventilation. Early diagnosis is critical, and broad-spectrum antivirals are being researched.
