The enigmatic virus responsible for Oropouche fever has been spreading beyond its initial confines since late 2023. This year alone, over 8,000 cases have been confirmed across the Americas, with Brazil experiencing the highest number.
In July, Brazilian health authorities reported two adult deaths due to the virus. These were the first fatalities since its discovery nearly 70 years ago.
Earlier this month, the Pan American Health Organization raised its risk assessment for Oropouche fever from moderate to high due to the virus’s increasing spread and recent fatal cases.
On August 23, the WHO reported that while the public health risk of the virus is high regionally, it remains low on a global scale. The US Centers for Disease Control and Prevention has recommended enhanced monitoring of individuals returning from areas affected by the virus.
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What is Sloth Fever Virus?
Oropouche/sloth dever is a virus belonging to the Orthobunyavirus genus. Unlike more widely recognized vector-borne viruses such as dengue, or Chikungunya, it is primarily transmitted to humans by a midge known as Culicoides paraensis, rather than mosquitoes.
For How Long has Oropouche Been Around?
The Oropouche virus was first identified in 1955 in Trinidad and Tobago, located in the Caribbean. It was later detected in Brazil in 1960, from a blood sample of a sloth. Since the 1960s, the virus has caused intermittent outbreaks in humans primarily within the Amazon region.
Why Are We Only Hearing About Sloth Fever Now?
What is notable about the current situation is the significant geographic expansion. The virus has affected a much larger number of municipalities and states than before, and it has spread beyond the Amazon region.
Is the Virus Becoming More Dangerous?
There is evidence suggesting that the Oropouche/sloth virus may be showing signs of increased danger, particularly with the recent discovery of antibodies against the virus in newborns with microcephaly, an abnormal small head. This finding hints at a possible link between Oropouche infection and neurological issues in babies. However, due to the study’s limitations, a direct relationship between the virus and these malformations during intrauterine development has not yet been established.
Evidence of mother-to-child transmission of the Oropouche virus has been confirmed in cases involving fetal and newborn deaths. In one instance, a pregnant woman with Oropouche symptoms experienced fetal death weeks later, and the virus was found in several of the fetus’s organs. In another recent case, a pregnant woman who tested positive for Oropouche gave birth to a baby that later died. The virus genome was detected in various tissues of the deceased infant, including the brain, during a post-mortem examination.
Two previously healthy young women with symptoms similar to severe dengue have died, marking the first reported cases of deaths. These individuals were not pregnant.
So yes, it is becoming dangerous.
What are Sloth Fever Virus Symptoms?
The symptoms of sloth fever virus resemble those of other arboviruses like dengue. They include –
- Fever,
- Headache,
- Muscle or joint pain,
- Pain behind the eyes,
- Vomiting, and
- Nausea.
While most cases are mild and typically resolve within seven to eight days, a few may progress to more severe forms, which can involve neurological or hemorrhagic symptoms.
How is Sloth Fever Transmitted?
Sloth fever, caused by the Oropouche virus, is primarily transmitted to people through the bites of infected midges (a type of small fly).
The CDC explains that the virus is typically transmitted in forested regions. Humans can become infected when they visit these forested areas and may then bring the virus into urban settings.
Sloth fever treatment and prevention
There are currently no vaccines or specific treatments for sloth fever, according to the CDC. The best preventive measure is to avoid insect bites.
To protect yourself, the CDC suggests using insect repellent, installing screens on windows and doors, and using fans outdoors to deter insects. Additionally, pregnant individuals are advised to avoid nonessential travel to areas where the virus is known to be present, such as Cuba and Brazil.
Alex Johnson is a seasoned writer and content creator based in New York City. With a passion for storytelling and an eye for detail, Alex covers a wide range of topics, including entertainment, technology, and lifestyle. When not writing, Alex enjoys exploring the vibrant cultural scene of NYC, attending live music events, and experimenting with new recipes in the kitchen. Connect with Alex on social media to stay updated on the latest articles and insights.