Hantavirus UK 2026: Symptoms, the MV Hondius Outbreak and When to Worry
⚡ Quick Answer
In the UK, the current risk from hantavirus is low. The news concerns an outbreak of Andes hantavirus on the cruise ship MV Hondius in the South Atlantic. The hantavirus strain found in UK rodents is different: it is Seoul hantavirus, which does not spread person to person. Since 2012, only 11 people in the UK have been confirmed with Seoul hantavirus. Two UK passengers from the cruise are well and isolating as a precaution. You should phone NHS 111 if you have a flu-like illness with severe muscle aches and have had recent contact with rodents or their droppings or have recently returned from South America. Go to A and E if you are breathless.
In early May 2026, headlines reported a hantavirus outbreak on a cruise ship, prompting understandable concern. The UK Health Security Agency (UKHSA) published a public explainer on 5 May 2026 in response to the situation involving the Dutch-flagged vessel MV Hondius. For most people in the UK, the risk remains low, but your questions are entirely legitimate.
Hantavirus is a family of viruses carried by rodents that can, in specific circumstances, cause serious illness in humans. If you are a pet-rat owner, a gardener who uses a shed, a parent or someone who has recently travelled, you want clear, calm facts. This article explains what happened on the cruise, why the UK risk is minimal, what symptoms look like, how the virus spreads in a UK context and precisely when you should contact your GP or NHS 111.
What happened on the MV Hondius and why hantavirus is in the news
The news stems from an outbreak on the MV Hondius, a cruise ship operating between Argentina and Cape Verde. In May 2026, passengers began falling ill. By 11 May, the World Health Organization had confirmed seven cases, with three associated deaths. Health authorities identified the strain as Andes hantavirus (ANDV), a virus found in South America. This particular strain is notable because it is the only hantavirus in the world with documented evidence of spreading from person to person, though this remains rare and typically requires sustained close contact.
The UKHSA confirmed that two passengers from the affected voyage returned to the United Kingdom. At the time of the UKHSA’s update on 5 May, these individuals were not reporting any symptoms. As a sensible precaution, they were self-isolating. The UKHSA took the step of publishing its public guidance to provide accurate information and manage concern, confirming that no onward transmission within the UK had been reported. The situation is being monitored, but for the UK public, the direct risk from this specific outbreak is considered low.
Why the UK risk is low (the Seoul vs Andes difference)
Understanding the low risk to the UK public requires looking at the specific viruses involved. The outbreak on the MV Hondius is caused by the Andes virus, a South American strain. The only hantavirus ever identified in UK rodents is a completely different virus called Seoul hantavirus. Seoul virus does not spread between people. It is carried by wild brown rats and, occasionally, by pet rats. UK rodents do not carry the Andes virus.
This means the exposure routes are entirely separate. The UKHSA risk assessment for the UK public remains low. To put UK incidence in perspective, since 2012 there have been only 11 confirmed human cases of Seoul hantavirus in the country. Of those eleven, nine were directly linked to contact with pet rats or rats bred as food for reptiles. The risk to the average person is not from walking in the countryside, but from specific, direct contact with rats or their fresh droppings. The two UK returnees from the cruise are isolated and well and no cases of Andes virus have originated in the UK.
🧬 ANDES vs SEOUL HANTAVIRUS 2026
| Feature | Andes (cruise) | Seoul (UK) |
|---|---|---|
| Region | South America | UK brown rats |
| Person-to-person | Yes (rare) | No |
| Main syndrome | HPS (lungs) | HFRS (kidneys) |
| UK cases since 2012 | 0 | 11 |
| UKHSA UK risk | Very low | Very low |
How hantavirus is caught and the classic high-risk mistake
Hantavirus transmission to humans almost always happens in one way: breathing in tiny particles that have been contaminated with rodent urine, droppings or saliva. When this material dries out, it can be disturbed by sweeping, vacuuming or even walking through an infested area, creating a fine aerosol that can be inhaled deep into the lungs. Less common routes include a rodent bite, getting contaminated material into a cut or a splash into the eye.
The classic high-risk activity in a UK setting is sweeping or vacuuming a shed, garage or barn that has old rodent droppings. This action aerosolises the virus, making inhalation likely. Historically, UK cases have overwhelmingly been linked to handling pet rats or feeder rats for reptiles or to cleaning outbuildings. For travellers, exposure to Andes virus in South America typically occurs when camping, staying in rural cabins or undertaking activities that disturb rodent-infested spaces. Simply seeing a rat in your garden in the UK does not constitute a meaningful exposure risk.
Hantavirus symptoms and the two-phase pattern
Hantavirus illness often follows a two-phase pattern and the incubation period is long, typically 2 to 4 weeks after exposure, but can range from 1 to 6 weeks. The initial phase, lasting about 3 to 7 days, looks much like a severe flu or gastroenteritis. Symptoms include:
- Fever
- Severe muscle aches (in the thighs, hips, back and shoulders)
- Extreme fatigue
- Headache
- Nausea, sometimes with vomiting, diarrhoea and abdominal pain
What happens next depends on the virus strain. Infections with New World viruses like Andes or Sin Nombre (found in the Americas) can progress to Hantavirus Pulmonary Syndrome (HPS). From around day 4 to 10, this involves a cough, worsening shortness of breath and rapid fluid build-up in the lungs, leading to low blood pressure. This is a medical emergency requiring intensive care, with a mortality rate of 30 to 40 percent without such support. Infections with Old World viruses like Seoul, which is the UK-relevant strain, can cause Haemorrhagic Fever with Renal Syndrome (HFRS). This affects the kidneys, causing kidney-area pain, reduced urine output and blood pressure changes and sometimes bleeding from the gums or nose. It is serious but generally less severe than HPS.
When to phone NHS 111, when to go to A and E and what to tell the GP
Knowing when to act is key. For most winter viruses, you would self-care at home. With hantavirus, the combination of symptoms and a specific exposure history changes the advice.
You should phone NHS 111 if you have a febrile illness with severe muscle aches AND you have had any of the following exposures within the last 6 weeks:
- Handling wild or pet rats
- Cleaning a shed or barn where you saw droppings
- Working with rats bred to feed reptiles
- Returning from a cruise or rural travel in South America, especially Argentina or Chile
You should go directly to A and E if you develop breathlessness on minimal exertion, blue lips, severe chest pain, confusion or notice a significant reduction in urine output.
When you speak to a GP, a nurse or NHS 111, be specific. Say: “I have a fever and severe muscle aches and I cleaned a shed full of droppings three weeks ago,” or “I returned from a cruise to Patagonia ten days ago and now have these symptoms.” Mentioning the rodent or travel exposure is critical, as it alerts the clinician to a rare possibility they would not otherwise consider for a common flu-like illness.
How to clean a shed, garage or rat cage safely (the no-aerosol method)
Safe cleaning is about avoiding aerosols. If you need to clean an area with rodent droppings, follow this method. First, open doors and windows for at least 30 minutes to ventilate the space before you enter. Wear disposable gloves and a well-fitted FFP3 mask, not a simple surgical mask. Do not dry sweep or vacuum under any circumstances.
Prepare a disinfectant solution: one part household bleach to ten parts water. Thoroughly soak the droppings, nesting material and soiled surfaces with this solution. Let it sit for at least five minutes. Afterwards, wipe everything up using damp paper towels. Place all waste in a sealed plastic bag and put it in an outdoor bin. Finally, wash your hands thoroughly with soap and water.
For pet rat owners: clean cages weekly using this wet method. Wash your hands with soap and water after every single time you handle your rats. Do not kiss your rats or allow them to nuzzle your face. Source any feeder rats from reputable, health-screened suppliers and never breed wild-caught rats.
⚠️ NEVER DO THIS
- Dry sweep droppings – this is the classic high-risk mistake
- Vacuum droppings – aerosolises virus particles
- Shake out old bedding sacks indoors
- Use a basic surgical mask (use FFP3)
- Clean without opening doors and windows for 30 min first
- Reuse paper towels – bag and bin them immediately
What this does NOT change and the bigger picture
The cruise outbreak is distressing, but it does not change the fundamental picture for the UK. Hantavirus is not a new virus, it has been recognised since the Hantaan virus was isolated in Korea in 1976 and the Sin Nombre virus was identified in the USA in 1993. It is not Covid-19. The UK strain does not spread through casual close contact. It is not transmitted by food, water, mosquitoes, dogs or cats.
There is no vaccine licensed for use in the UK and no specific antiviral treatment has been proven reliably effective. Medical care is supportive: this means providing intravenous fluids, oxygen, mechanical ventilation if the lungs fail and dialysis if the kidneys are affected. Early hospital admission improves outcomes.
For most people in the UK, the most relevant practical takeaway is the correct method for cleaning sheds and pet cages. The largest ongoing exposure group in this country remains pet-rat owners and users of reptile feeder rats, who can dramatically reduce their risk with consistent hygiene.
Frequently Asked Questions
Can I catch hantavirus from a rat I see in my garden in the UK?
Simply seeing a rat in your garden is not an exposure. Infection requires breathing in aerosolised dried droppings or urine or a bite. While UK wild brown rats can carry Seoul hantavirus, human cases are rare-only 11 confirmed since 2012. The sensible response is not to panic, but to avoid attracting rats by not leaving out bird food and by storing rubbish in sealed bins.
I have pet rats. Should I get rid of them?
No, but you should practice strict hygiene. Wash your hands with soap and water after every handling session. Do not kiss your rats. Clean their cage weekly using the wet disinfectant method described above, never by dry sweeping. Source any feeder rats from reputable suppliers. The risk is small with sensible precautions and UKHSA has not recommended getting rid of pet rats.
I was on the MV Hondius. What do I do?
Follow the guidance from UKHSA. You should have been contact-traced. As a precaution, self-isolate if instructed. Monitor your temperature daily for six weeks from when you disembarked. If you develop any fever, severe muscle aches, headache or breathlessness in that period, phone NHS 111 immediately and mention your travel on the MV Hondius. Go to A and E if you become breathless.
How long does hantavirus take to show symptoms?
The incubation period is usually 2 to 4 weeks after exposure, but the full range is 1 to 6 weeks (or 1 to 45 days). This long window makes it difficult to link symptoms to a specific event without knowing about rodent or travel exposure. If you had a potential exposure, you should remain alert for symptoms for up to six weeks afterwards.
Is there a vaccine or treatment for hantavirus in the UK?
There is no vaccine licensed in the UK and no specific antiviral drug that reliably works. Treatment is supportive care in hospital: this includes intravenous fluids, oxygen, ventilation if needed for breathing support and dialysis if the kidneys begin to fail. This is why it is so important to tell NHS 111 or a doctor about any rodent or travel exposure-it ensures you get the right assessment faster.
Does hantavirus spread from person to person?
Almost always, no. The Seoul hantavirus strain present in the UK does NOT spread between people. The Andes hantavirus from South America is the only strain with proven person-to-person transmission and this usually requires sustained, close household contact. The cruise outbreak is a rare exception. For a typical UK case of Seoul virus, no household isolation is needed.
✅ The verdict
The situation on the MV Hondius is serious, but for residents of the UK, the risk of hantavirus remains low. The virus causing the outbreak is not the one found in UK rodents. The key is proportionate caution, not panic.
Sensible everyday actions are your best defence: keep rodents out of your home and outbuildings, clean any droppings using the wet bleach method with an FFP3 mask and wash your hands thoroughly after handling pet rats. If you develop a fever with severe muscle aches within six weeks of cleaning a shed, handling rats or returning from South America, mention that specific exposure when you phone NHS 111. Hantavirus is rare in the UK and with these simple steps, it will stay that way. For more health guidance, read about the NHS 1-minute pembrolizumab injection rollout, the 2026 UK annual prescription charge and exemptions guide, and the MHRA finasteride and dutasteride safety warning.
This article is informational only and does not replace personalised advice from your GP, pharmacist, or another qualified healthcare professional.
