In recent months, federal health officials reported that over 20 individuals returning to the United States from Cuba have contracted a virus transmitted by insects. All cases involve Oropouche virus disease, commonly referred to as sloth fever.
Fortunately, there have been no fatalities, and there is currently no indication of the virus spreading within the United States. However, health officials are advising U.S. physicians to remain vigilant for this infection in travelers arriving from Cuba and South America.
To provide further context, here is an overview of the illness that prompted this alert:
What is Oropouche virus?
Oropouche is a virus endemic to tropical forest regions. It was first discovered in 1955 in a 24-year-old forest worker on Trinidad, named after a nearby village and wetland area. The virus has been colloquially referred to as sloth fever due to its initial identification in a three-toed sloth, leading researchers to believe that these animals play a significant role in its transmission between insects and other wildlife.
How is the Oropouche virus transmitted?
The Oropouche virus is transmitted to humans primarily through the bites of small flies known as midges, as well as certain species of mosquitoes. Infections in humans have typically occurred in forested regions, where individuals are thought to facilitate the virus's spread to urban areas. However, there is no evidence of direct person-to-person transmission.
What is the current case count?
Since late last year, the Oropouche virus has been linked to significant outbreaks in the Amazon regions where it was previously known, as well as in newly affected areas across South America and the Caribbean.
Approximately 8,000 locally acquired cases have been documented in Bolivia, Brazil, Colombia, Cuba, and Peru. Additionally, some travelers have been diagnosed with the virus in the United States and Europe.
According to the U.S. Centers for Disease Control and Prevention, there have been 21 reported cases in the U.S. — 20 in Florida and one in New York — all involving individuals who had traveled to Cuba. European health authorities have also reported 19 cases, predominantly among travelers.
What are the symptoms and treatments?
The symptoms may resemble those of other tropical illnesses such as dengue, Zika, or malaria. Common indicators include fever, headaches, and muscle pain, while some individuals may also experience diarrhea, nausea, vomiting, or skin rashes.
Certain patients may experience recurring symptoms, and approximately 5% may develop more severe complications, including bleeding, meningitis, and encephalitis. Although fatalities are rare, there have been recent reports of deaths among two otherwise healthy young individuals in Brazil.
Currently, there are no vaccines available to prevent these infections, nor are there any medications to alleviate the symptoms.
Are there additional concerns?
In Brazil, health officials are examining reports suggesting that infections could be transmitted from a pregnant woman to her fetus, reminiscent of the Zika virus outbreaks nearly ten years ago.
The CDC has advised pregnant women to refrain from non-essential travel to Cuba and has recommended that all travelers take precautions against insect bites, such as using insect repellent and wearing long-sleeved clothing and long pants.