Dozens of people returning to Florida from Cuba have been infected with a virus transmitted by insects this year, the state health department reported.
They all had Oropouche virus disease, also known as sloth fever.
None have died, and there is no evidence that it's spreading in the United States. But federal health officials are warning doctors to be on the lookout for the infection in travelers coming from Cuba and South America.
Oropouche is spread to humans by small biting flies called midges and by some types of mosquitoes. Humans have become infected while visiting forested areas and are believed to be responsible for helping the virus make its way to towns and cities, but person-to-person transmission hasn't been documented.
A Tuesday alert on Oropouche from the Centers for Disease Control and Prevention comes out as Florida health officials continue to combat mosquitoes that may carry dengue fever and West Nile virus. The state currently has alerts or advisories for mosquito-borne illnesses in 13 counties.
“The emergence of Oropouche virus, even though the cases are travel-related, is a cause for concern,” Steve Harrison, manager for Orange County Mosquito Control said in a statement. “It highlights the interconnectedness of global health and the potential for mosquito-borne diseases to spread in other parts of the world.
“We have intensified our efforts to control mosquito populations and prevent the establishment of Oropouche virus, as we did to mitigate the spread of dengue fever.”
How many cases have there been?
According to the Florida Department of Health, 30 travel-related cases have been reported in the state this year through Saturday. All patients had traveled to Cuba in an endemic area two weeks prior to onset.
Ten of those cases were added in the agency's report for Aug. 18-24.
Miami-Dade County reported 14 cases, five were in Hillsborough, two in Orange, Lee and Polk, and one in Broward, Duval, Palm Beach, Pasco and Sarasota.
The U.S. Centers for Disease Control and Prevention on Tuesday said one case was reported in New York, also by someone who traveled to Cuba.
European health officials said they had found 19 cases, nearly all among travelers.
Beginning late last year, the virus was identified as the cause of large outbreaks in Amazon regions where it was known to exist, as well as in new areas in South America and the Caribbean.
About 8,000 locally acquired cases have been reported in Bolivia, Brazil, Colombia, Cuba and Peru.
What are the symptoms, treatments and background?
Oropouche is a virus that is native to forested tropical areas. It was first identified in 1955 in a 24-year-old forest worker on the island of Trinidad, and was named for a nearby village and wetlands.
It has sometimes been called sloth fever because scientists first investigating the virus found it in a three-toed sloth, and believed sloths were important in its spread between insects and animals.
Symptoms can seem similar to other tropical diseases like dengue, Zika or malaria. Fever, headaches and muscle aches are common, and some infected people also suffer diarrhea, nausea, vomiting or rash.
Some patients suffer recurring symptoms, and 1 in 20 can suffer more severe symptoms like bleeding, meningitis and encephalitis. It is rarely fatal, though there are recent reports of deaths in two healthy young people in Brazil.
There are no vaccines to prevent infections and no medicines available to treat the symptoms.
What else should I know?
A Level 2 travel health alert for Cuba was issued by the CDC. A Level 2 alert advises travelers to take enhanced health precautions.
A Level 1 travel alert was indicated for countries in South America, particularly Bolivia, Brazil, Colombia and Peru. That advises travels to take normal precautions.
In Brazil, officials are investigating reports that infections might be passed on from a pregnant woman to a fetus — a potentially frightening echo of what was seen during Zika outbreaks nearly a decade ago.
The CDC has recommended that pregnant women avoid nonessential travel to Cuba and suggested all travelers take steps to prevent bug bites, such as using insect repellents and wearing long-sleeved shirts and long pants.
Health News Florida's Rick Mayer contributed to this report.