In 1955, a forest worker in Trinidad and Tobago contracted a fever. The worker recovered fully, though the disease persisted, with outbreaks occurring in northern South America and nearby coastal islands. The movements of humans pose challenges for those hoping to reduce the risks associated with any infectious agent, as is the case with the current outbreak of the Oropouche virus.

Outbreak

The Oropouche (pronounced “O-ro-push”) virus is the causative agent of a 2024 disease outbreak in Cuba, spreading through the Caribbean and Brazil. Historically, transmission of the virus occurred primarily within the Amazonian Basin of the continent of South America, where it also infects sloths and “new world” non-human primates. Over the past seventy years, the increased prevalence of infections corresponds with deforestation and climate change in its endemic region. This year, over 10,000 individuals have contracted the disease and the current serotype has killed two young, healthy women—the first known deaths related to Oropouche. The Pan American Health Organization (PAHO) and World Health Organization (WHO) monitor the developing situation and assist with training medical and laboratory professionals to identify infections.

Symptoms

Like influenza, symptoms are characterized by fever, weakness, headache, and fatigue. Some instances involve neurological issues such as photophobia and can worsen to include encephalitis and meningitis. While the course of the disease may take approximately two weeks, in sixty percent of cases, patients report full relapse into illness after “recovery”, extending their time to recover for over a month. 

Updates in Transmission

While initially thought only to be transmitted through insects that bite, ranging from mosquitoes and sandflies to biting midges that affected a wide variety of hosts beyond humans, Oropouche is now known to be transmissible by unprotected sexual contact with infected body fluids. Fluids like semen pose a danger of transmission and infection for at least a week after symptoms resolve.

Risk to the United States

In 2024, approximately one hundred cases were documented in the United States. Most instances are in Florida, and all United States examples of the disease during the current outbreak are related to travel to and from Cuba. For this reason, Cuba travel poses the highest risk of contracting the disease.

Treatment

There are no treatments for infection with the Oropouche virus. Without an anti-viral medication available, treatment options include supportive care only. The approach includes preventing dehydration, resting, consuming NSAIDs for pain management, and using antipyretics to reduce fever. Unfortunately, no medical interventions prevent maternal-to-fetal transmission, resulting in miscarriage, sometimes in a matter of days after a pregnant woman contracts the virus.

CDC Dashboard

The CDC ArboNET surveillance system (previously discussed here) has a dashboard to monitor cases and follow the ongoing outbreaks and case numbers within the United States. 

Editor: Lucy Cafiero