Hantavirus refers to a strain of viruses carried by rodents, primarily transmitted to humans through inhalation of airborne particles from dried rodent droppings.

Infections typically occur when the virus becomes airborne from a rodent's urine, droppings, or saliva, according to the US Centers for Disease Control and Prevention (CDC).

Though rare, it can also spread through rodent bites or scratches.

There is no specific treatment for hantavirus infections. The CDC recommends supportive care to treat symptoms that could include oxygen therapy, mechanical ventilation, antiviral medications and dialysis.

Patients with severe symptoms may need to be admitted to hospitals in intensive care units. In severe cases, some may need to be intubated.

• Read more: What is the hantavirus that has been confirmed on an Atlantic cruise ship?

Image source, Getty Images

Three people have died after a suspected hantavirus outbreak on a cruise ship. Here's what we know - and don't know - so far:

What we know

• Three fatalities: Three people have died, the World Health Organization (WHO) says. This includes a 70 and 69-year-old Dutch husband and wife. Repatriation efforts are under way. The body of the third individual is still on board the ship
• British national in hospital: One British national aged 69 is in intensive care in Johannesburg, South Africa - the only confirmed case of hantavirus
• Two others sick on board: Cruise ship operator Oceanwide Expeditions says two crew members require urgent medical care but have not been allowed to disembark in Cape Verde for treatment
• Name of cruise ship: The outbreak took place on the MV Hondius cruise ship, which was travelling with about 150 passengers from Argentina and is now anchored at port off the capital of Cape Verde

What we don't know

• Total number of cases: One case has been confirmed in a laboratory, with five more suspected cases under investigation, WHO tells the BBC

• How the outbreak started: Infections occur when the virus becomes airborne from a rodent's urine, droppings, or saliva, and less commonly spread through rodent bites or scratches - transmission between people is rare
• More cases could emerge: A microbiologist tells the BBC it takes symptoms anywhere from one to eight weeks to emerge and asks "are we going to see more people coming down with the disease in the next days and weeks?"

Epidemiologist Michael Baker tells the BBC passengers who had the suspected hantavirus would have been infected before they got on board the cruise ship due to the virus's long incubation period.

He added that it was rare for humans to get the hantavirus and "very unusual" for people to develop the disease on a cruise ship.

"That's the worst possible place to get seriously ill," Professor Baker says.

He says anyone with symptoms on board should be "rapidly evacuated" and taken to hospital with intensive care to increase their chances of survival.

When asked what steps should be taken next, Professor Baker says the outbreak needs to be "investigated throughly" to see if there were any preventable factors, including traveller itineraries to see if they were exposed to high risk environments.

Hantavirus is not a common virus but is severe, Prof Paul Griffin, the Director of Infectious Diseases at Mater Health Services in Australia, told the Australian Broadcasting Corporation.

He said there were around 150,000-200,000 cases around the world every year.

It is "exceedingly rare" for the virus to be transmitted from person to person, and usually spreads from a common source, like rodent droppings or urine.

But he added "what we're seeing on this cruise ship - is a bit suspicious that there might be some transmission".

Cruise ships, he said, are "an environment that's very conducive to the transmission of infections" due to having lots of people in a confined space for a prolonged period of time.

Since Covid, hygiene practices have improved and it is "extremely unusual" for hantavirus to have infected passengers, Griffin said.

Microbiologist Siouxsie Wiles told the BBC hantavirus is detected in lots of different places and outbreaks are often sporadic and "little", tending to "fizzle out".

She said it was unclear how people were exposed to the virus.

"Human to human transmission is very rare, in fact in the medical literature people have argued whether it's real or not," she said.

"The question is - is this a group of people who have been exposed to infected rodents, or has one person been exposed and then is transmitting to others?"

Wiles said food could have been contaminated with hantavirus.

She said the time between people being exposed to hantavirus and showing symptoms could be anywhere from one to eight weeks.

"With this incubation period are we going to see more people coming down with the disease in the next days and weeks?"

The MV Hondius is at anchor off the port of Praia, the capital of Cape Verde, ship tracking sites show.

Footage shows it anchored in the sea, with the coast in the background.

Image source, Getty Images

As a reminder, hantavirus hit the headlines last year.

The wife of Oscar-winning actor Gene Hackman died from a respiratory illness linked to hantavirus in March 2025.

Medical investigators said Betsy Arakawa contracted Hantavirus Pulmonary Syndrome (HPS), a life-threatening lung condition.

It is one of two severe illnesses that can be caused by hantavirus and, according to the Centers for Disease Control and Prevention (CDC), has a mortality rate of about 38%.

The second illness, Haemorrhagic Fever with Renal syndrome, is more severe and primarily affects the kidneys.

There is no specific treatment for hantavirus infections.

Hackman died of natural causes about a week after his wife. He passed away at his Santa Fe home from coronary artery disease, with advanced Alzheimer's disease a contributing factor.

In a statement to the BBC, Oceanwide Expeditions says it is investigating if hantavirus is linked to the three deaths on the cruise.

"A strain of hantavirus has been identified in one passenger who was previously medically evacuated from the vessel and is currently being treated in intensive care in Johannesburg," it says, referring to the 69-year-old Briton.

"Hantavirus has not been confirmed in the two symptomatic individuals currently on board."

It says it is looking into the "exact cause" of the deaths and "any possible connection".

"We are currently establishing the full facts and working on appropriate medical care, screening and next steps," it says.

Oceanwide Expeditions tells the BBC it expects to provide further updates as soon as more information becomes available.

Image source, Oceanwide Expeditions

The MV Hondius is 107.6m long, with a breadth of 17.6m and a draft - how deep the vessel sits in the water - of 5.3m.

There are 80 cabins on board, in which up to 170 passengers and 57 crew, 13 guides and one doctor can stay, according to cruise operator Oceanwide Expeditions.

Two passengers sleep in most of the classes of cabins available but some have three and four berths in a space measuring 15.3 sq m.

The outbreak was reported aboard the MV Hondius cruise ship, which was travelling from Argentina to Cape Verde.

The MV Hondius is run by tour company Oceanwide Expeditions.

According to an itinerary on its website, MV Hondius departed from Ushuaia in Argentina on 20 March and was expected to complete its journey on 4 May in Cape Verde, an island nation in the Atlantic west of Africa.

It is described as a 107.6m (353ft) polar cruise ship, with space for 170 passengers in 80 cabins, along with 57 crew members, 13 guides and one doctor.

A separate statement from the South African Department of Health says the ship was carrying around 150 tourists.

Dutch authorities are leading efforts to repatriate two symptomatic people aboard the ship, Oceanwide Expeditions says.

"The body of the deceased individual is also planned to be included in this repatriation, along with a guest closely associated with the deceased," it says, adding the guest is not symptomatic.

To help the sick people return home to the Netherlands, Oceanwide Expeditions says it needs authorisation and support from authorities in Cape Verde, an island nation in the Atlantic west of Africa.

"We are in close contact with those directly affected and their families and are providing support where possible," it says.

In an update on the situation on board the MV Hondius, cruise operator Oceanwide Expeditions says it has not been authorised by Cape Verde to allow crew members needing urgent medical assistance to disembark.

It says health officials have visited the ship, located off the coast of Cape Verde, and assessed "the two symptomatic individuals".

They are yet to make a decision regarding the transfer of these individuals into medical care in Cape Verde," Oceanwide Expeditions says in its statement.

It adds its priority is to ensure the two crew members checked by Cape Verde health officials "receive adequate and expedited medical care".

A spokesperson from South Africa's Department of Health says the ship was carrying about 150 tourists from various countries, and left Ushuaia in Southern Argentina about three weeks ago.

They say it was heading to the Canary Islands with multiple stops in between, including mainland Antarctica, the Falklands, South Georgia, Nightingale Island, Tristan, St Helena, Ascension, and Cape Verde.

Image source, AFP via Getty Images

Earlier, the World Health Organization (WHO) said that one hantavirus case had been confirmed in a laboratory, with five more suspected cases under investigation.

A spokesperson from the South African Department of Health now says the confirmed case is a 69-year-old British national.

He says the patient from the UK "became ill while the ship was travelling from St Helena to Ascension Island and was transferred from a hospital in Ascension to a South African private health facility in Sandton for medical attention".

"His laboratory test results came back positive for hantavirus," the spokesperson says.

South Africa's Department of Health spokesman Foster Mohale says the 70-year-old man "suddenly became ill" as the cruise ship sailed from the city of Ushuaia in Argentina to the island of St Helena.

Mohale adds that the man presented with "fever, headache, abdominal pain, diarrhoea", before dying on arrival in St Helena.

A spokesman for the South African Department of Health tells the BBC the 70-year-old cruise passenger who died is "awaiting repatriation to the Netherlands".

Foster Mohale says the man's wife collapsed while "trying to connect to a flight to her home country of the Netherlands" and "unfortunately passed away" in hospital in the Kempton Park area.

The UK Foreign Office tells the BBC it is monitoring reports closely, and is "ready to support British nationals" following the suspected hantavirus outbreak.

"We are in touch with the cruise company and local authorities," a spokesperson adds.

As we reported in an earlier post, one British national, aged 69, is in intensive care in Johannesburg, South Africa.

The World Health Organisation (WHO) has told the BBC earlier that three people have died following the suspected outbreak. One case has been confirmed, with five more suspected cases under investigation, it says.

Hantavirus infections are typically linked to environmental exposure, the World Health Organization (WHO) says.

This includes "exposure to infected rodents’ urine or faeces".

In rare cases, WHO says the virus can also spread between people, and can lead to "severe respiratory illness".

It requires "careful patient monitoring, support and response", WHO says.

The World Health Organization (WHO) tells the BBC that "detailed investigations" into the suspected hantavirus cases are "ongoing, including further laboratory testing".

"Medical care and support are being provided to passengers and crew. Sequencing of the virus is also ongoing," it adds.

"WHO is facilitating coordination between Member States and the Ship’s operators for medical evacuation of two symptomatic passengers, as well as full public health risk assessment and support to the remaining passengers on board."

Image source, Getty Images

South African authorities have told the BBC that the first person to show virus symptoms was a 70-year-old passenger who died on board the MV Hondius cruise ship.

His body is now on the island of Saint Helena, a British territory in the South Atlantic.

His 69-year-old wife also became ill on board and was evacuated to South Africa, where she died in a Johannesburg hospital.

The husband and wife were a Dutch couple, AFP news agency reports citing a source close to the case.

Speaking anonymously, the source tells AFP the third fatality was still on board the ship, and discussions were under way to decide whether two other sick passengers should be placed in isolation in hospital in Cape Verde.