Viral hemorrhagic fevers (VHFs) are a group of illnesses caused by viruses that damage your blood vessels and can cause severe bleeding. Some hemorrhagic fever viruses can also cause mild symptoms like body aches and fatigue. Examples of VHFs include Ebola, dengue, Marburg and yellow fever. They’re most common in parts of Africa, Asia and South America.
Viral hemorrhagic fevers (VHFs) are a group of viral infections that can cause uncontrolled bleeding. They spread in many ways, including through insect bites and contact with body fluids of infected people or animals.
The viruses in this group range in severity. Many of them cause mild illness. But all of them can damage your blood vessels and interfere with your blood’s ability to clot, leading to life-threatening complications.
Viral illnesses that can cause hemorrhagic fevers include:
Different VHFs spread in different parts of the world. Most are found in parts of:
Only hantaviruses cause VHFs in the U.S., Canada and Europe. Hantaviruses are a subtype of bunyavirus. Various types cause hantavirus pulmonary syndrome (in the Americas) and hemorrhagic fever with renal syndrome (in Europe).
Symptoms of VHFs vary depending on the disease. Early in the illness, they often include:
In severe cases, VHFs can also cause:
Experts don’t fully understand the ways that hemorrhagic fever viruses cause severe bleeding. There’s evidence that the viruses damage your blood vessels, causing them to leak. They can also interfere with blood clotting, meaning your body can’t stop bleeding when it should.
Several types of viruses can cause viral hemorrhagic fevers, including:
Not all species of these viruses cause hemorrhagic disease. For instance, Zika is caused by a flavivirus, but it doesn’t damage your blood vessels the way VHFs do.
The viruses that cause hemorrhagic fevers each spread in different ways. Some ways you can get infected include:
Risk factors for getting an infection with a hemorrhagic fever virus vary by the type of VHF. You might be at higher risk if you:
Many VHFs carry a high risk of severe illness and complications in pregnant people.
VHFs can cause life-threatening complications, including:
Providers might suspect you have a VHF based on your symptoms and certain risk factors (like your travel history). They’ll also test samples of your body fluids for signs of viruses. To get samples and perform tests, they might do:
There’s no specific cure for viral hemorrhagic fever. But there are antiviral treatments for a few VHFs. Most of the time, healthcare providers treat you by managing your symptoms and keeping your condition stable. Treatments might include:
You can take steps to reduce your risk of VHFs by:
If you’re severely ill, your provider will treat you in the hospital to manage your symptoms and any complications. You might be isolated from others to prevent spreading the virus.
Yes, you can recover from milder forms of hemorrhagic fevers. Lassa, dengue and yellow fever often cause mild symptoms, but severe forms can be deadly. Others, like Marburg and Ebola, are often fatal.
The mortality (death) rate varies for hemorrhagic fevers, depending on the virus causing it. For instance, Marburg and Ebola are the deadliest hemorrhagic fevers, with average mortality rates higher than 40%. But only about 1% of people with Lassa or dengue fevers die from them.
If you live in or have recently visited an area that has VHFs (or you have other risk factors), contact your healthcare provider if you develop symptoms. They’ll give you recommendations on how to take care of yourself and if you need to seek additional treatment.
Go to the nearest emergency room right away — and let them know you might have a VHF — if you have severe symptoms, including:
It might be helpful to ask a healthcare provider:
A note from Cleveland Clinic
Viral hemorrhagic fevers can cause very serious illness. But the most severe forms are very rare. If your work, hobbies or travel put you at risk for VHF, talk to a healthcare provider about what you can do to protect yourself. They can let you know if there are preventive measures available and what to do if you develop concerning symptoms.
Last reviewed by a Cleveland Clinic medical professional on 09/14/2023.
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