Oropouche virus disease
What is Oropouche virus disease?
Oropouche virus disease is caused by the Oropouche virus, which is primarily spread through the bite of infected midges, but it can also be spread by mosquitoes. Oropouche virus has been found to circulate in Central and South America, and the Caribbean.
The Culicoides paraensis midge is the primary vector (transmitter) of the disease. This midge is widely distributed across the Americas. The European Centre for Disease Prevention and Control (ECDC) have reported that there is a lack of evidence as to whether European midges or mosquitoes could transmit the virus, but the primary vector (Culicoides paraensis midge) is not found in Europe.
Oropouche virus was first detected in 1955 in Trinidad and Tobago, and over the last 25 years, cases of Oropouche have been identified in many countries in the Amazon region. In 2024 to date, outbreaks have been reported in Cuba, Brazil, Colombia, Peru and Bolivia. Oropouche virus had never previously been detected in Cuba before May 2024.
In June and July 2024, imported cases of Oropouche virus disease were reported in Europe for the first time. Nineteen imported cases have been reported to ECDC in June and July 2024, 18 of these were imported from Cuba and one from Brazil.
How is Oropouche virus disease spread?
Oropouche virus is spread to people primarily by the bite of an infected biting midge (Culicoides paraensis). It can also be spread by some mosquitoes. After biting an infected person or animal, the midge or mosquito can then transmit the virus to a susceptible person.
What are the symptoms of Oropouche virus disease?
Symptoms can include an acute onset of fever with headache, nausea, vomiting, chills, muscle and joint pains.
Symptoms usually appear between 3 and 8 days after the bite and typically last from 2 to 7 days. Severe disease is rare from Oropouche virus, but it may result in aseptic meningitis, haemorrhages or neurological symptoms. The prognosis for recovery after Oropouche infection is good and fatal outcomes (death) are extremely rare. The disease symptoms are like dengue fever.
Are there treatments available?
There are no specific medicines to treat Oropouche virus disease and there are currently no vaccinations to prevent Oropouche virus disease. The symptoms of Oropouche virus disease can be treated by drinking fluids to prevent becoming dehydrated, rest, and taking medicine as recommended by your doctor to reduce pain and fever. For people with more severe symptoms, hospitalisation may be needed.
How is Oropouche virus disease prevented?
The most effective way to protect yourself from Oropouche virus disease is to prevent bites from biting midges and mosquitoes when travelling to countries where Oropouche transmission occurs. Measures to prevent bites by mosquitoes are similar to those to prevent bites by midges.
Are there risks during pregnancy?
The risk of Oropouche virus during pregnancy is currently being investigated. Brazil has recently reported possible cases of Oropouche virus disease being passed from a pregnant woman to a foetus and potentially resulting in congenital abnormalities and foetal death. These potential risks during pregnancy and effects to the foetus are still under investigation and have not been confirmed.
What is the advice for pregnant travellers?
ECDC have published a threat assessment brief on Oropouche virus disease cases imported into the European Union. ECDC advise that due to the potential risks of Oropouche virus during pregnancy, the following is recommended:
- Pregnant people who intend to travel to areas where there is ongoing transmission or reported transmission of Oropouche should be provided with comprehensive information on the risk associated with Oropouche infection and prevention strategies.
- Pregnant people planning to travel to epidemic countries where transmission is ongoing or has been reported should always seek pre-travel health advice to assess the risk of infection based on the local situation.
- Pregnant people should pay strict attention to personal protective measures against midge and mosquito bites, should they choose to travel. See further advice on preventing bites.
What do I do if I am travelling to an area where Oropouche virus infection is circulating?
ECDC advises that for people travelling to affected areas, the greatest risk of becoming infected is probably by a bite from an infected Culicoides paraensis midge. This midge bites during the day and easily enters houses, with peaks in activity after sunrise and before sunset. Personal protective measures to reduce the risk of bites should be implemented when outdoors. Protective measures should be implemented indoors, if houses that are not adequately screened (with fine-mesh screens on doors and windows) or air-conditioned. See further advice on preventing bites.
What do I do if I’m returning to Ireland from an area where Oropouche virus is circulating?
If you become ill when you return to Ireland, you should contact your doctor for assessment and let him/her know of your recent travel to an affected area.
Last updated: 3 September 2024