Overview of Outbreak
Oropouche virus disease outbreaks have been reported in multiple countries across South America and the Caribbean, including as recently as 2023–2024. Travel-associated cases have been identified among U.S. residents; however, there is no evidence of local transmission within the United States. Surveillance is conducted through ArboNET, the national arbovirus surveillance system, which provides weekly updates on reported cases. For the most up-to-date information on countries with recent or past Oropouche virus transmission, clinicians should refer to the CDC site.
What is the epidemiology of Oropouche?
Oropouche virus is an arthropod-borne, single-stranded, negative-sense RNA virus first identified in 1955. It is transmitted primarily through the bite of infected biting midges (Culicoides spp.), though some mosquito species can also serve as vectors. Since its discovery, the virus has been reported in several regions of South America, Central America, and the Caribbean, where it remains an important cause of arboviral disease.
How does Oropouche present in children?
Initial symptoms often resemble those of other mosquito-borne diseases and include fever, headache, arthralgia, myalgia, rash, nausea and vomiting, chills, and fatigue. Approximately 60% of individuals infected with the virus develop symptoms. While most recover within a week, about 70% may experience a relapse of symptoms days to weeks after initial recovery.
Neuroinvasive disease may occur in up to 4% of patients. Symptoms include intense occipital pain, dizziness, confusion, lethargy, photophobia, nuchal rigidity, and nystagmus.
Oropouche virus infection symptoms overlap with those of other arboviral diseases, such as dengue, chikungunya, and Zika viruses. The disease can also mimic malaria or rickettsial infection. Based on the travel and exposure history of the patient, these illnesses may also need to be considered in the differential diagnosis.
How is Oropouche diagnosed?
The optimal test depends on the duration of illness at the time of testing. Molecular evidence of the virus can be detected in serum by PCR within the first week of illness, and serological evidence can be detected after 6 days of infection. Specimens can be submitted using general CDC arboviral testing guidance.
For patients with neuroinvasive disease, cerebrospinal fluid can also be sent for testing. specimens.
What are common laboratory findings for a patient with Oropouche?
Lymphopenia, leukopenia, elevated C-reactive protein, and mildly elevated liver enzymes have been documented. Cerebrospinal fluid abnormalities, such as pleocytosis and elevated protein, have been noted in patients with neuroinvasive disease.
How do you treat Oropouche?
There are no effective antivirals or vaccines are available for Oropouche virus. Management focuses on supportive care (rest, fluids, and use of analgesics and antipyretics. Acetaminophen is the preferred first-line treatment for fever and pain.
How do you prevent Oropouche?
There is no vaccine for Oropouche virus. Avoiding exposure to infected insects is the key to prevention. This includes avoiding travel to impacted areas, especially for those at high risk of complications such as pregnant women, and taking measures to avoid insect bites.
EPA-registered insect repellents and wearing light-colored long-sleeved shirts and long pants while outside are recommended. EPA-registered repellents should be labeled for flies, biting flies, or Culicoides (biting midges, punkies, granny nippers, and no-see-ums). For young children, ensure the specific repellent is safe, as not all repellents are recommended are safe in all age groups. Window and door screens can help prevent midges and mosquitoes from entering your home.
Learn more about mosquito-borne illnesses
