The Oropouche virus, an infectious disease primarily transmitted by the tiny biting insects known as midges, is capturing the attention of public health officials worldwide.
With more than 10,000 cases reported this year in South America and the Caribbean, the virus is now making its way to the United States.
Data from the Centers for Disease Control and Prevention (CDC) confirms 94 documented cases in the US for 2023-2024, all linked to travel. Among these cases, two involved serious brain infections, such as encephalitis and meningitis.
Dr. Peter Chin-Hong, a specialist in infectious diseases at the University of California, San Francisco, has been discussing the potential threat posed by the Oropouche virus.
The Oropouche virus was first discovered in the village of Oropouche, located in Trinidad.
The first recognized outbreak occurred in 1961 in Brazil and has since impacted several countries in Central and South America, including Panama, Peru, Colombia, and Bolivia.
The virus is spreading more widely in 2023, with Brazil and neighboring nations reporting over 10,000 cases. Cuba has also reported its first case, and the virus has been identified in travelers returning to the United States.
Not related to COVID-19, the Oropouche virus shares similarities with other viruses known to cause brain infections in humans, such as the California encephalitis virus and the La Crosse virus.
Transmitted mainly by midges, these small biting flies are often referred to as “no see-ums” due to their tiny size.
Infected midges can transmit the virus to humans, and they are also known to bite animals like monkeys, sloths, and birds, which helps sustain the transmission cycle. Mosquitoes might also play a role in spreading the virus, though midges are the primary vector.
The virus can also be transmitted from mother to child and potentially through sexual contact, as it has been found in the semen of infected individuals.
After being bitten by an infected midge, symptoms typically develop within 3 to 10 days. Approximately 60% of those infected experience sudden fever with chills, headaches, muscle and joint pain, and a rash. Other symptoms may include conjunctivitis, gastrointestinal issues, and bleeding. The illness usually lasts about five days.
Although Oropouche infection is rarely fatal, two deaths out of approximately 8,000 cases were reported by the CDC’s Morbidity and Mortality Weekly Report.
Currently, there are no specific treatments available for the Oropouche virus. Treatment is supportive, focusing on managing symptoms, as no vaccines offer protection.
Dr. Chin-Hong does not expect the virus to reach pandemic proportions in the US. However, he anticipates a continued increase in cases from travelers returning from affected regions in Central and South America and the Caribbean.
