In a follow-up on the Oropouche fever outbreak in Brazil, Brazil health officials report 8,901 confirmed cases from the beginning of the year through April 22.
The state of Espirito Santo leads all states with 5,826 cases, followed by Rio de Janeiro state with 1,466, Paraíba state with 618 cases, Ceará state with 510 cases and Minas Gerais with 388 cases.
In all of 2024, Brazil reported 13,791 confirmed cases. In 2023, 832 cases were recorded.
In a study recently published in The Lancet Infectious Diseases, researchers say, “Alongside the dengue and chikungunya viruses, Oropouche virus is probably most common virus transmitted by insect bites in Latin America”.
“Our data shows that Oropouche virus is massively under-diagnosed in Latin America”.
They also note, “The consequences of an infection, including on unborn babies, require further investigation. It’s not yet clear whether there are parallels with the Zika virus. Overall, however, it appears to cause harm to unborn babies less frequently than Zika.”
Oropouche is a disease caused by Oropouche virus. It is spread primarily through the bites of infected biting midges (small flies) and mosquitoes. Oropouche virus has been found in semen. It is unknown if Oropouche can be spread through sex.
Symptoms of Oropouche include headache, fever, muscle aches, stiff joints, nausea, vomiting, chills, or sensitivity to light. Severe cases may result in neuroinvasive disease such as meningitis.
Symptoms typically start 3–10 days after being bitten and last 3–6 days. Most people recover without long-term effects.
“When it comes to protecting against Oropouche virus, and also against other tropical viruses like dengue and Zika, it’s worth wearing long clothes and using insect repellent, such as DEET or picaridin,” says the virologist. “Mosquito nets can also offer protection if their mesh is sufficiently fine.” The virus is primarily transmitted by flies commonly known as “no-see-ums” – tiny mosquitoes up to 3 millimeters long, which are able to pass through the mesh of conventional mosquito nets.
There is no vaccine for Oropouche virus, nor is there a specific treatment for Oropouche fever.