Three fatalities in Hantavirus outbreak on Dutch cruise ship.

Three people have died and a further five people have been infected in an outbreak of Hantavirus on the Dutch cruise ship MV Hondius, according to a press release issued by the World Health Organization on 8 May 2026. The disease, which is caused by the Virus Orthohantavirus andesense, is a zoonotic disease (disease with a reserve in a wild Animal population which sometimes spreads to Humans) causing a hemorrhagic or pulmonary fever. It is not easily passed from Human-to-Human, but can do so when people are living together in close conditions in an environment such as a cruise ship.

The outbreak is thought to have begun with an 70-year-old male Dutch national who boarded the ship at Ushuaia, on the Argentinian part of Tierra del Fuego, on 1 April 2026, after spending three months touring Argentina, Chile, and Uruguay. This patient developed symptoms at sea, and died on 11 April before the ship reached any port. He is considered a probable case, as no microbiological tests were carried out. 

The MV Hondius, a 106.7 m Polar Class 6 vessel, designed for luxury touring in polar regions with a minimal environmental impact, which was hit by Hantavirus outbreak in April and May 2026. Oceanwide Expeditions.

The second patient to develop the disease was the original patient's 69-year-old widow, who had been travelling with the first patient and joined the ship with him. She developed gastrointestinal symptoms at sea, and left the ship when it arrived at Saint Helena on 24 April, and flew to Johannesburg the following day, where she boarded a flight to Amsterdam, where her condition deteriorated rapidly, causing her to be removed from the plane and moved to a local hospital, where she died on 26 April. She was confirmed as being infected with Orthohantavirus andesense by polymerise chain reaction testing carried out by the South African National Institute for Communicable Diseases.

The third patient, another adult male, started to show symptoms on 24 April, and was evacuated from the ship when it put into Ascension Island on 27 April. This patient was also airlifted to Johannesburg, where he is being treated in an intensive care unit. This patient was also confirmed as being infected with Orthohantavirus andesense by polymerise chain reaction testing.

A fourth patient, and adult female German national, developed a fever on 28 April, while the ship was sailing between Ascension Island and the Cape Verde islands, and died of pneumonia on 2 May, before the ship made it to port. This patient was later confirmed to have died of Hantavirus by post-mortem examination.

The fifth patient, the ship's doctor, began to develop symptoms on 30 April, and was confirmed as having Hantavirus by polymerise chain reaction testing when the ship reached Cape Verde on 6 May, and was airlifted to the Netherlands, where he is currently being treated in an isolation unit. 

The sixth patient, a guide employed on the ship, reported mild respiratory and gastrointestinal symptoms on 27 April. He was also diagnosed with Hantavirus infection by polymerise chain reaction testing when the ship reached Cape Verde and airlifted to the Netherlands.

A seventh patient, who disembarked from the ship at St Helena on 22 April and flew home to Switzerland via South Africa and Qatar, began to show symptoms on 1 May. He immediately self-reported to medical authorities in Switzerland, and is now being treated in an isolation unit there.

An eighth patient, who disembarked from the ship at Tristan da Cunha in the South Atlantic on 14 April, began to show symptoms on 28 April. He is now being treated in isolation, although results of testing for the Virus have yet to be returned.

A ninth patient with Hantavirus-like symptoms was evacuated at Cape Verde and airlifted to Germany, but was later found not to be infected.  Efforts are still being made to trace 32 other patients who disembarked at Saint Helena and dispersed to a variety of countries before the nature of the outbreak was understood. After leaving Cape Verde the ship sailed to the Canary Islands, where it was met by medical personnel from the World Health Organization and a variety of countries, where both passengers and crew were screened for the Virus before being allowed to travel on to their home countries, where they will be required to undergo a period of isolation. A skeleton crew and medical personnel remained on the ship while it was sailed to the Netherlands to be thoroughly disinfected. 

Stops made by the MV Hondius during the outbreak. On 11 May, the ship was en route to Rotterdam. Wikipedia.

A flight attendant on the Johannesburg-Amsterdam flight from which the second patient was removed also later developed symptoms, and was admitted to a hospital in Amsterdam. Two Singaporean nationals who had been on the ship and subsequent flight from Saint Helena to Johannesburg were tested for the Virus after one developed Hantavirus-like symptoms, but neither was found to be infected. Attempts are still being made to trace passengers from both fights.

Hantavirus infections are caused by triple single-stranded negative-sense RNA Viruses of the genus Orthohantavirus. These Viruses are typically found in Rodents, with 28 species known, each of which infects a different species of Rodent. These Viruses occasionally jump species and infect Humans, where they break down into two groups, Old World Hantaviruses, which can cause a hemorrhagic fever accompanied by a severe kidney infection, and New World Hantaviruses, which cause a severe respiratory disease.

Structure of the Andes Hantavirus. Lexi Schoonover/Hope College/Wikimedia Commons.

The Andes Hantavirus, Orthohantavirus andesense, is found in Long-tailed Pygmy Rice Rats, Oligoryzomys longicaudatus, a wild Rodent found in the southern Andes of Chile and Argentina, where it does not appear to produce any symptoms. It can be transmitted to Humans through the inhalation of  aerosols that contain rodent saliva, urine, or feces, through the consumption of contaminated food, or by being bitten or scratched by a Rat.

A Long-tailed Pygmy Rice Rat, Oligoryzomys longicaudatus, the wild vector of the Andes Hantavirus. Yamil Hussain/Wikimedia Commons.

There is no effective treatment or vaccine for Hantavirus, and the disease is best prevented by using cleanliness and good hygiene to keep Rodents from entering Human dwellings or workplaces. If this fails a pest control consultant should be used to remove the Rodents. Placing infected patients in intensive care with fluids and, if necessary, artificial respiration, can help, but even with these precautions about 30% of patients typically die. Patients who have been infected with the disease and survive are generally immune to further infections with the same Virus.

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Assessing the impact of a Highly Pathogenic Avian Influenza Virus upon the Elephant Seal population of South Georgia.

The Southern Elephant Seal, Mirounga leonina, is the largest species of Pinniped (the group which includes Seals, Sea Lions, and Walruses) and an important predator in the circumpolar Southern Ocean. They breed annually, coming ashore on Sub-Antarctic islands in the southern summer. The males emerge first, carving out territories in bouts of competitive fighting, which they then defend for the rest of the season. The pregnant females emerge later, settling in the territories of one of the males, to form harems, groups of females defended by a male. Here they give birth, wean their cub, and finally, at the end of the season, come into oestrus, allowing the male to mate with them before they return to the sea.

Elephant Seals on a beach on South Georgia Island. George Lemann/South Georgia Museum.

There are four genetically distinct populations of Southern Elephant Seals, the  Peninsula Valdés Population, which breeds on the Argentinian coast, the South Georgia Population, which breeds on the islands of the South Atlantic, including South Georgia, South Sandwich Island, and the Falkland Islands, the Macquarie Population, which breeds on the Islands of the South Pacific, and the Heard and Kerguelen Population, which breeds on the islands of the southern Indian Ocean, including the Crozet and Prince Edward archipelagos. Of these populations, the South Georgia Population is thought to be the largest, containing about 54% of the global population.

Because Southern Elephant Seals live in remote locations, data on their populations is difficult to gather, making it difficult to compare populations directly. The Peninsula Valdés Population, possibly the easiest to monitor, is known to have grown by between 1 and 3.4% each year for the past five decades. The South Georgia Population is thought to be stable. The Macquarie Population is thought to have shrunk throughout the twentieth century, going through a slight recovery in the early twenty first century, before starting to shrink again more recently. In the Indian Ocean, the sub-population on Marion Island, in the Prince Edward Archipelago, has declined by 83% since 1950, which represents an annual decline of 5.8%, the Îles Crozet sub-population shrank by 5.4% per year between 1970 and 1990, but more recently have been growing at about 5.1, while the Îles Kerguelen sub-population shrank by 47% between 1952 and 1987, then rose by almost 1% per year between 1987 and 2009, and has been rising at about 1.6% annually more recently.

Influenza A Viruses are Negative-strand RNA Viruses which circulate naturally in both Animal and Human populations, causing seasonal flu. Occasionally a particularly more virulent strains of Influenza A appear, causing large mortality rates among affected species, such as the notorious Spanish Flu, which may have killed over 100 million people between 1918 and 1920. Avian Influenza is a form of Influenza A Virus which first appeared on poultry farms in China in late 2003, rapidly spreading to other farms across East Asia during 2004, causing mass deaths of poultry everywhere it reached. In 2005 it caused a mass death of wild Birds on Qinghai Lake in central China, a lake which is used as a stopover for many migratory Bird species. Later that year cases began to appear in Europe and Africa. While mainly affecting Birds, Avian Influenza can infect Mammals, including Humans, however, although it can be fatal, it seldom spreads between members of most Mammal species, limiting the size of any outbreaks. However, some Mammals appear to be more vulnerable than others with the Virus spreading without the need for further contact with Birds. Such vulnerable Mammals include Cows and Seals.

Negative stained transmission electron micrograph showing  recreated 1918 influenza Virions that were collected from supernatants of 1918-infected Madin-Darby Canine Kidney cells cultures 18 hours after infection. Centres for Disease Control and Prevention/Wikimedia Commons.

Since this time several strains of Avian Influenza have appeared, which have been loosely divided into Highly Pathogenic Avian Influenza Viruses, which typically kill more than 75%  of the Birds in any infected population, and Low Pathogenic Avian Influenza Viruses, which typically kill less than 75%. The 2.3.4.4b clade is a Highly Pathogenic Avian Influenza Virus which first appeared in Europe in 2020, and has subsequently spread to North and South America, where it caused mass deaths among Seabirds and Marine Mammals in 2022. In September 2023, a Brown Skua, Stercorarius antarcticus, on Bird Island, South Georgia, was found to have died as a result of infection with Highly Pathogenic Avian Influenza Virus, with the infection subsequently spreading to Gentoo Penguins, Pygoscelis papua, Snowy Albatrosses, Diomedea exulans,Antarctic Fur Seals, Arctocephalus gazella, and Southern Elephant Seals. In 2024, the Virus was also confirmed on Îles Crozet and Îles Kerguelen in the southern Indian Ocean.

During the 2023/4 breeding season, Southern Elephant Seals on South Georgia were monitored for Highly Pathogenic Avian Influenza Virus via sample collecting at sites which could be accessed from the sea, in combination with observations made from research vessels and cruise ships, suggested that the colony could have lost as many as 97% of its pups.

In a paper published in the journal Communications Biology on 13 November 2025, Connor. Bamford, Nathan Fenney, Jamie Coleman, Cameron Fox-Clarke, and John Dickens of the British Antarctic Survey, Mike Fedak of the Sea Mammal Research Unit at University of St Andrews, Peter Fretwell, also of the British Antarctic Survey, Luis Hückstädt of the Centre for Ecology and Conservation at the University of Exeter, and Phil Hollyman, again of the British Antarctic Survey, and of the School of Ocean Sciences at Bangor University, present a study of the three largest Southern Elephant Seal numbers on South Georgia, based upon photographic data collected by an uncrewed aerial vehicle.

In October 2024, 4373 female Southern Elephant Seals were observed at St Andrews Bay, whereas 6305 were recorded in October 2022. At Hound Bay, 1154 females were observed in 2024, compared to 1901 in 2022. This represents a 47% decline in the number of breeding females at these two sights between 2022 and 2024, and a 33.7% decline compared the long term population average (taken between 1958 and 2022). Bamford et al. extrapolate for that this would represent in a total fall in the number of breeding females across South Georgia of about 55 000.

Locations of the largest breeding colonies of Southern Elephant Seals, Mirounga leonina, on South Georgia. Sites of the three largest breeding colony beaches of Southern Elephant Seals, Mirounga leonina, on South Georgia (by total number of breeding females from the 1995 census where aerial imagery was collected in 2022 and 2024, Bamford et al. (2025).

Bamford et al. note that there are gaps in our knowledge of Elephant Seal breeding, which affect how their data should be interpreted. It is possible that the reduction in the number of breeding females represents a direct measure of the rate of adult mortality suffered by Southern Elephant Seals on South Georgia as a result of Highly Pathogenic Avian Influenza Virus infection. However, female Seals whose pups die tend to leave the breeding beaches fairly quickly, and it is therefore possible that many Seals left beaches in 2023 before coming into oestrus and mating, and therefore did not return in 2024 to raise pups. It is unclear how female Elephant Seals return to the breeding population after losing a pup, although it seems unlikely that they simply stop breeding altogether. 

Another potential disruption to Elephant Seal breeding behaviour comes from sea ice. In 2023 sea ice in the Southern Atlantic cover was the lowest ever recorded at that time (2024 subsequently produced even lower ice levels). This potentially had an impact on the Elephant Seals, as sea ice has a stabilising effect on the Southern Ocean, tending to suppress the formation of storms, as well has having an impact on the ecology of many prey species. However, Bamford et al. do not believe that this is likely to have caused a sufficient disruption to the Seals to explain the observed population drop, given the wide area over which they typically forage.

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One dead and thousands without power as Atlantic Storm Amy batters Ireland.

A man in his forties has died in Letterkenny, County Donegal, in what local police have described as a 'weather-related incident' associated with Atlantic Storm Amy, which has battered Ireland, the United Kingdom, and parts of Western Europe on Thursday 2 to Saturday 4 October 2025. Around 185 000 homes, businesses, and farms in the Republic of Ireland lost their electricity supplies due to the storm, with a further 50 000 losing power in Northern Ireland, 62 000 in Scotland, 1000 in northern England, and about 300 in Wales. Rail services have been disrupted in Ireland and Scotland, and all of London's Royal Parks have been closed to protect the public from storm-related hazards. 

Flooding in County Monaghan, Northern Ireland, caused by Atlantic Storm Amy. Monaghan County Council.

Ocean storms form due to heating of air over the sea in tropical zones. As the air is heated the the air pressure drops and the air rises, causing new air to rush in from outside the forming storm zone. If this zone is sufficiently large, then it will be influenced by the Coriolis Effect, which loosely speaking means the winds closer to the equator will be faster than those further away, causing the storm to rotate, clockwise in the northern hemisphere and anticlockwise in the southern hemisphere.

A building collapse in Glasgow, Scotland, caused by Atlantic Storm Amy. BBC.

Whilst the high winds associated these storms is extremely dangerous, the real danger from such storms is often the flooding. Each millibar drop in air pressure can lead to a 1 cm rise in sea level, and large storms can be accompanied by storm surges several meters high. This tends to be accompanied by high levels of rainfall, caused by water picked up by the storm while still at sea, which can lead to flooding, swollen rivers and landslides; which occur when waterlogged soils on hill slopes lose their cohesion and slump downwards, over whatever happens to be in their path.

Storm damage in County Antrim, Northern Ireland, caused by Atlantic Storm Amy. Charles McQuillan/Getty Images.

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British Divers Marine Life Rescue successfully return stranded Killer Whale to water in the Orkneys.

A Killer Whale, Orcinus orca, stranded on a beach on Sanday in the Orkney Islands, Scotland, has been successfully returned to the sea by volunteers from British Divers Marine Life Rescue. The Whale was spotted by members of the public on a beach in the Bay of Newark on Monday 4 January 2020, who called the local coordinator for the group. On arrival the Animal was found to be a juvenile about 3.4 m in length, and probably a male (although the volunteers concentrated on rescuing the Animal rather than determining its sex). The Whale, which was on its side, was righted to enable it to breath better, and refloated on the incoming tide. The Whale is thought to have been about 3-4 years old, at which age it would no longer be depemdant on its mother, and a member of the North Isles 27s Pod, which is commonly seen in the area.

 

A young Killer Whale, Orcinus orca, stranded on a beach on Sanday in the Orkney Islands, on Monday 4 January 2020. British Divers Marine Life Rescue.

Killer Whales are the largest members of the Dolphin Family, Delphinidae, and have a global distribution. They are highly inteligent and adaptable Animals, able to take a wide range of prey, with different populations often specialising in hunting different prey items. It is possible that Killer Whales are a cluster of cryptic species (species which appear identical but which are genetically distinct and reproductively isolated) rather than a true biological species (single global population with all members potentially able reproduce with one-another), which makes their conservation status difficult to assess. Killer Whales are thriving in some areas, but in others are threatened by Human activities, such as heavy shipping, fishing, and offshore drilling. This means that if the species is in fact a species cluster, then the populations of each biological species might be quite small and potentially threatened.

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