What You Need To Know About Sloth Fever Virus

Another virus has reached U.S. soil. This time it's the Oropouche virus — also known as sloth fever because the virus was first found in 1955 in the blood of a sloth. According to Scientific American, Oropouche had infected people and animals primarily in the Amazon, but the virus has been slowly spreading to countries as far north as Cuba.

The Centers for Disease Control and Prevention (CDC) has reported 52 U.S. Oropouche disease cases, but all these cases came from people who have returned from travel to the Amazon basin and other areas. So far, no cases of sloth fever have been transmitted locally in the United States.

Viruses like COVID-19 and the common cold spread when people make direct contact with infected air droplets coming in through their mouth or nose. Other viruses like Zika spread through the blood, primarily when people are bitten by a mosquito that carries the virus. The Oropouche virus similarly spreads through some types of mosquitoes but its carriers are mostly midges, which are small flies nicknamed "no-see-ums." It can also be spread from a pregnant person to the fetus.

People who've been infected by the Oropouche virus often will develop a fever accompanied by headaches, muscle and joint pain, or chills. Some people might experience light sensitivity, dizziness, or nausea. A small percentage of people develop symptoms of neuroinvasive disease — such as confusion, lethargy, or involuntary rapid eye movements — after experiencing the initial fever. Although symptoms last less than a week, more than half of people can experience a relapse of symptoms weeks later. It's rare for people to die of the Oropouche virus.

If you've recently traveled to a region where Oropouche transmission is likely and you experience these symptoms, your doctor will need to take a blood test to look for viral RNA or antibodies. The CDC says there aren't any vaccines or treatments for Oropouche, so the best way to manage the sloth fever virus is to treat the symptoms through rest, fluids, and acetaminophen (Tylenol). Because dengue fever has similar symptoms as Oropouche, avoid aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) until a blood test has confirmed Oropouche.

The CDC issued an advisory on August 16 alerting about the spread of the Oropouche virus beyond the Amazon region. If you plan to travel to any country that has a travel health notice for a viral outbreak spread by mosquitoes or midges, you should protect your skin with an insect repellant registered by the Environmental Protection Agency. It's also best to cover yourself by wearing long-sleeve shirts and pants (Yes, a mosquito can bite through clothing). When choosing accommodations, find places with air conditioning or windows with screens. Remember that symptoms of Oropouche might not show up until later, so you could still spread the virus after you return from travel.

Cuba is currently at a Level 2 travel notice, which means there is an ongoing Oropouche outbreak. You should take extra steps to protect yourself from bug bites while in the country. To prevent a possible spread in the United States, the CDC also suggests protecting yourself from bug bites for at least three weeks upon returning home. Pregnant women should reconsider nonessential travel to Cuba.

Bolivia, Brazil, Colombia, and Peru are also seeing cases of Oropouche, so you'll need to take measures to prevent bug bites if you plan to travel to those countries as well.