The story so far:

Following a hantavirus outbreak on the MV Hondius expedition cruise ship in early May, in which three deaths were reported and at least five others were infected, global attention has once again turned to the group of viruses. Hantavirus had made headlines last year following the passing of Betsy Hackman, the wife of renowned American actor Gene Hackman.

What happened on the ship?

The Dutch expedition cruise ship was travelling from Ushuaia in Argentina across parts of the South Atlantic towards Cape Verde and the Canary Islands when cases were identified among both the passengers and the crew.

The World Health Organization (WHO) said 147 passengers and crew were onboard, and 34 passengers and crew had previously disembarked. It said that as of May 8, there were eight cases (six confirmed and two probable cases) reported. Three of them died (two confirmed and one probable) after contracting the Andes strain of hantavirus. Several others were hospitalised with symptoms including fever and breathing difficulties.

After confirmed and suspected cases had been identified among passengers after they left the ship and travelled to different countries, health authorities in Singapore, Switzerland, South Africa, Spain, and the U.S. began tracking and monitoring passengers.

What is hantavirus?

Hantaviruses are a group of viruses mainly carried by rodents such as rats and mice. Human beings can get infected after coming into contact with infected rodent urine, saliva, or droppings, especially while cleaning or disturbing contaminated areas, which can release virus particles into the air.

Hantavirus infections can affect either the lungs or the kidneys. Some strains can cause hantavirus pulmonary syndrome, a severe respiratory illness, while others can lead to haemorrhagic fever with renal syndrome, affecting the kidneys and blood vessels. WHO states that even though most hantaviruses do not spread from one human to another, the Andes virus strain found in parts of South America has shown some human-to-human transmission, usually among close contacts.

Why are health agencies concerned now?

The outbreak linked to the MV Hondius cruise ship drew attention because passengers travelled across several countries before the infection was identified. WHO reported that cases were characterised by fever, gastrointestinal symptoms, pneumonia, respiratory distress, and shock. Reacting to fears of another pandemic, officials from WHO and the Disease Control and Prevention have stressed that hantavirus spreads very differently from viruses such as COVID-19 and is far less transmissible.

What are the symptoms?

WHO states that symptoms usually appear between one and eight weeks after exposure. Early symptoms are often flu-like and can include fever, muscle aches, fatigue, headache, chills, nausea, vomiting, abdominal pain, and dizziness.

In severe cases, the infection can affect the lungs, causing coughing, chest tightness, breathing difficulty, and fluid build-up in the lungs. Some forms of the disease can also affect the kidneys and blood vessels, leading to kidney complications or bleeding problems. Since the symptoms can resemble illnesses such as influenza, COVID-19, dengue, or pneumonia, diagnosis may sometimes be delayed. Even though infections remain rare overall, severe respiratory forms of hantavirus infection can be dangerous, particularly without early medical care.

Who is at risk?

People living or working in rodent-prone environments face the highest risk. Farmers, forestry workers, campers, construction workers, and people cleaning poorly ventilated or abandoned buildings are vulnerable. Health agencies also advise caution while handling pet rodents or entering rodent-infested spaces.

Is there a treatment or cure?

WHO notes that early diagnosis and timely medical attention can significantly improve outcomes. Prevention is important, particularly through rodent control, proper sanitation, and safe cleaning practices in potentially contaminated environments.

Currently, there is no specific antiviral cure or approved vaccine for hantavirus infection. Treatment mainly focuses on supportive medical care, including oxygen therapy, fluid management, and intensive care support during severe illness. Some patients may require mechanical ventilation.

Could this become another pandemic?

Public health agencies say current evidence does not suggest a COVID-19-like global pandemic scenario. WHO has repeatedly stated that the overall risk to the wider public remains low and that hantavirus does not spread easily between humans like airborne viruses such as influenza or SARS-CoV-2.

The outbreak has also drawn attention to zoonotic diseases — infections that spread from animals to humans — and highlighted the importance of staying prepared as global travel and human-animal interactions increase. At the same time, WHO and other health agencies have stressed that stronger surveillance, quicker reporting, testing systems, and coordination between countries are helping health authorities respond effectively.