Genus Culicoides, a type of midge that can spread Oropouche, or sloth fever, via Scott Bauer, U.S. Agricultural Research Service
Floridians traveling to Cuba account for all of the 90 Oropouche, or sloth fever, cases reported in the state, but researchers are trying to determine whether the mosquito-borne illness could spread locally.
The total number of cases in the United States is 94, meaning the Sunshine State has been a hotspot for importation of the virus. California, Colorado, Kentucky, and New York have reported one case each, according to the Centers for Disease Control and Prevention.
Before 2023, Oropouche outbreaks had been confined to the Amazon basin but have since spread locally in South America and the Caribbean and now, through returning travelers, Florida.
While no one has contracted Oropouche in Florida, the CDC awarded $1 million to the University of Florida to evaluate whether specific mosquitoes found in the state could carry the strain of Oropouche circulating in Cuba, an agency spokesperson wrote to the Phoenix via email.
Additionally, mosquito control programs across the state are working on response plans in case Oropouche infiltrates the mosquito population, said Kiera Lucas, a board member of the Florida Mosquito Control Association, in a phone interview with Florida Phoenix.
“The challenging thing about Oropouche when it comes to mosquito control is that it’s also spread by Culicoides, which are basically no-see-ums, and the particular species of no-see-ums that it’s spread by is found in hardwood forests. It can also be transmitted by certain mosquito species,” said Lucas, who is based in Collier County. “So, in terms of how mosquito control would respond to this, we would have to also respond to the no-see-um population.”
Miami-Dade County has had the most cases with 53, according to the state’s latest arbovirus report. Other counties where cases have emerged include Hillsborough (12); Lee (5); Polk (4); Broward, Orange, and Pasco (3 each); Palm Beach (2); Collier, Duval, Marion, Sarasota, and St. Lucie (one each).
While Oropouche doesn’t have a specific treatment, the CDC recommends people with the virus rest, hydrate, and take medicines such as Ibuprofen or aspirin to help with the symptoms.
The most common symptoms for U.S. patients have included fever, muscle aches, headache, fatigue, and joint stiffness. Others who contracted the virus reported diarrhea, abdominal pain, and vomiting, according to the CDC.
Oropouche has led to fetal deaths and possible birth defects in Brazil and the virus was detected in a patient’s semen, which raised concern about the possible sexual transmission, according to the CDC.
Other mosquito-borne illnesses in Florida
Lucas said that other mosquito-borne illnesses such as dengue and West Nile virus are also of concern after hurricanes Helene and Milton made landfall in Florida in late September and early October, causing floods. Out of 67 counties in Florida, 28 are under mosquito-borne-illness alerts and advisories.
So far this year there have been 21 cases of West Nile virus, 66 cases of locally transmitted dengue, and 758 cases of travel-associated dengue, according to the state’s latest arbovirus report.
“Because of Florida’s tropical and subtropical climate, especially South Florida, we can sustain mosquito populations year-round, and mosquito-borne disease is always a concern for Florida, and it’s usually the gateway for mosquito-borne diseases such as dengue virus or Oropouche,” Lucas said.
To avoid contracting viruses from mosquitos, people should avoid outdoor activities during dawn and dusk, wear long sleeves and pants, use (EPA)-registered insect repellents, and drain standing water.