What you should know about the Oropouche virus, also known as “sloth fever”
The virus was first discovered in 1955 and is endemic in Central and Eastern South America.
U.S. health officials are warning travelers about a potentially deadly insect-borne virus called sloth fever that has infected 21 U.S. citizens returning from Cuba and thousands more in South America and the Caribbean.
As of August 1, more than 8,000 cases of Oropouche virus disease had been reported in Brazil, Bolivia, Peru, Colombia and Cuba. Cases have also emerged in the United States and Europe among travelers returning from Cuba and Brazil, the Centers for Disease Control and Prevention reported Wednesday.
What is laziness fever?
Sloth fever is a colloquial term for infections with the Oropouche virus, which first appeared in Trinidad and Tobago in 1955. The virus is transmitted through mosquito bites and is endemic in Central and Eastern South America.
During the current outbreak, cases have been identified in Brazil, Bolivia, Peru, Colombia and Cuba. In the United States, cases have been limited to travelers returning from Cuba to Florida or New York. While the Oropouche virus is colloquially known as sloth fever, the disease can also be transmitted to rodents, monkeys and birds.
What are the symptoms of sloth fever?
Most infections are mild, but two otherwise healthy Brazilian women, ages 24 and 21, died after contracting the Oropouche virus, officials said. Symptoms, which appear three to 10 days after infection, include fever, chills, headache, and muscle and joint pain or stiffness. Other symptoms may include vomiting, diarrhea, fatigue, rash, stomach pain, sensitivity to light, and red eyes. Doctors treat symptoms with rest, fluids, and acetaminophen for fever and pain.
Public health officials say they are particularly concerned about cases of mother-to-fetus transmission.
There is no vaccination or antiviral treatment for oropouche.
Can the virus be transmitted from mother to fetus?
Laboratory tests found five cases in which an infected mother apparently transmitted the virus to a fetus. One fetus died and four others reported microcephaly, a birth defect in which the baby's head is smaller than normal. The CDC said the reports suggested the virus was linked to “fetal death and possible congenital malformations,” which “raised concerns about the threat posed to human health by Oropouche virus.”
According to the CDC, these cases underscore the urgency of containing the spread in the United States and other largely untouched regions.
I'm pregnant. Should I avoid traveling to certain regions?
Because of the potential risk of pregnant women transmitting the virus to the fetus, the CDC recommends that doctors and other health care professionals warn pregnant women who plan to travel to areas where cases have been transmitted of the dangers. Pregnant travelers should take steps to avoid insect bites and consider postponing travel to regions where sloth disease outbreaks are occurring, officials said.
Where were the US cases reported?
A total of 20 Florida residents and one New York resident who returned from Cuba were confirmed to be infected with the Oropouche virus.
Most patients were examined at the onset of their illness, but three people experienced recurrent symptoms. The average age of the patients was 48 years. The most common symptoms were fever, muscle aches, headache, fatigue, and joint stiffness or pain. Other patients reported diarrhea, stomach pain, nausea, vomiting, rash, back pain, and bleeding.