Oropouche virus disease is a lesser-known tropical infection that’s been spreading across Central and South America in recent years. If you’re planning to travel to the region, or are just curious about this emerging health concern, here’s everything you need to know.
How you catch Oropouche virus disease
Oropouche virus disease is caused by the Oropouche virus (OROV). This virus spreads through insect bites – specifically tiny insects called midges. The risk of these tiny insects (also called Culicoides paraensis) biting is highest at dawn and dusk, but they are active throughout the day, with a secondary peak in activity around midday. Midges found in the UK and wider Europe do not currently spread Oropouche virus disease.
In urban areas, some mosquitoes have also been found to carry the virus, though midges remain the main culprit.
The illness is sometimes known as ‘sloth fever’ as the virus naturally occurs in sloths, as well as primates and birds. It is a vector-borne disease (illness spread by insects) like malaria, Zika or dengue fever.
An important form of transmission currently being investigated is from mothers to babies during pregnancy, which may cause congenital or developmental abnormalities. This is still being studied, but it’s something pregnant women travelling to Central and South America should be aware of.
Due to the recent finding of OROV in semen, specialist advice should be sought; more information on factors to consider is available here.
Regions affected
Oropouche virus disease was first discovered in the 1950s in Trinidad and Tobago, and is endemic to the Amazon region.
Historically, it has been seen in countries across Central and South America, including Brazil, Peru, Argentina, Bolivia, Colombia, and Panama. In 2024 a number of outbreaks occurred in these countries, as well as in Cuba and Barbados. In 2025, cases were identified in Venezuela for the first time.
Signs and symptoms of Oropouche virus disease
Symptoms typically show up 4 to 8 days after a bite. Onset of the illness is sudden, and symptoms are similar to those of other vector-borne diseases including chikungunya, dengue, Zika virus disease and malaria :
- fever
- headache
- joint pain
- muscle aches
- chills
- nausea and vomiting
- rash
- sensitivity to light
- dizziness
- pain behind the eyes
Symptoms typically last up to a week but in about 6 out of 10 cases they can come back days or even weeks later. Most people recover fully, but in rare cases it can lead to more serious conditions like meningitis, Guillain-Barre syndrome or encephalitis (inflammation of the brain). The first ever deaths linked to the virus were reported in Brazil in July 2024, where, sadly, 2 people died.
If you’ve recently returned from an affected region and have symptoms, it’s important to seek medical attention and make sure you mention your travel history.
Treatment
Unfortunately, there’s no specific medicine to treat Oropouche virus disease. Like many viral infections, treatment is about managing symptoms: rest, drink plenty of fluids, and take paracetamol or other over-the-counter meds to ease fever and pain.
If you develop severe symptoms, especially anything that might suggest brain involvement (like severe headache, confusion, or neck stiffness), seek medical attention immediately.
Prevention
There is no vaccine for this disease, so prevention involves avoiding insect bites.
Here are some simple ways you can protect yourself:
- use insect repellent containing at least 50% DEET
- wear long-sleeved shirts and long trousers, especially during dawn and dusk
- stay in places with air conditioning or window screens with fine mesh to keep out midges.Use insecticide-treated fine mesh bed nets if you’re sleeping in areas without screens – standard bed nets are less effective against biting midges, as these insects are small and can pass through the netting.
- chemical insecticides sprayed inside and outside can also help deter midges
- remove standing water around your accommodation where insects might breed
Special considerations for pregnant women
If you’re pregnant and considering travel to affected areas, it is important to discuss this with your GP or travel clinic before you go. While we are still learning about the risks of OROV during pregnancy, the potential for mother-to-child transmission – and impact on the foetus – means extra caution is necessary.
Your healthcare provider can help you weigh the risks and benefits of travel, and if you do go, they can advise you on the best protection strategies.
How we are monitoring developments
Oropouche virus disease is part of a larger pattern we’re seeing with vector-borne diseases expanding their geographic range. Climate change, increased travel, and urbanisation all play roles in how these diseases spread.
We are monitoring the situation closely and working to understand more about the virus and how to prevent its spread.
Visit a travel health clinic
For most people, catching Oropouche virus disease results in mild symptoms. But if you are planning a trip to Central or South America, it’s worth being aware of the risks and taking appropriate precautions.
Visiting a travel health clinic at your GP practice or local pharmacy 4 to 6 weeks before you travel will enable you to make sure you are up to date with necessary vaccination and have the latest advice on ways to protect your health when you’re travelling.
There’s more information about this and other diseases in the ‘Outbreaks’ section of the National Travel Health Network and Centre (NaTHNaC). There are also country-specific pages where you can find out about wider guidance relating to your destination.
