Viral hemorrhagic fevers, or VHFs, are caused by four different groups of viruses: Arenaviridae (which can cause Lassa fever), Bunyaviridae (which can cause Rift Valley Fever), Filoviridae (which can cause Ebola and Marburg), and Flaviviridae (which can cause yellow fever and dengue).
All of these viruses affect multiple organs, cause damage to your blood vessels, and can affect your body’s ability to regulate its basic functions.
While some viral hemorrhagic fevers only cause mild ailments, others, such as Marburg and Ebola, are known for causing severe illness and can even be fatal.
These viruses use animals (such as flies) are a carrier but can also be passed from human to human through contact with feces, saliva and other body fluids.
There currently are no vaccines for all the different sorts of viral hemorrhagic fevers, therefore, it is recommended to avoid contact with host vectors and humans who are infected with the virus especially when traveling to areas where these diseases are common.
Symptoms will depend upon the type of VHF that has been contracted.
Oftentimes, initial symptoms will include fatigue, fever, muscle aches, exhaustion, loss of strength, and dizziness.
In those who have contracted a severe VHF, signs of bleeding underneath the skin, as well as bleeding of internal organs, will become apparent. Bleeding can also occur from orifices, such as the ears, eyes, and mouth. These patients may also develop nervous system malfunction, delirium, seizures, shock, kidney failure, and coma.
Viral Hemorrhagic Fevers (VHFs) refer to a cluster of diseases that are caused by one of several viruses. They generally result in multi-organ system failure of the patient, including damage to the vascular system and hemorrhage. VHFs are caused by four different kinds of viruses that manifest in diseases like Dengue Fever, Ebola, Rift Valley Fever, Lassa, Marburg and Yellow Fever.
Viral fevers must begin in an animal host called the natural reservoir. These animals, particularly rodents, bats and insects such as ticks and mosquitoes are generally confined to certain areas of the world and are concentrated in places like West Africa, parts of South America and certain regions of Asia.
The viruses that cause VHFs are all RNA viruses. VHFs are transmitted through contact from an infected animal, inhalation of infected urine or fecal matter, blood to blood contact or through semen. Humans are not natural carriers of these specific RNA viruses, but once a human is infected, human to human transmission is possible.
There currently aren’t any treatments that are effective against the viral hemorrhagic fevers that are found around the world.
Doctors will focus on providing supportive therapy and keeping the body as strong as possible until the virus has taken its course. Ribavirin, which is an antiviral medication, as well as convalescent-phase plasma, have been implemented with success in treating certain viral hemorrhagic fevers.
The viruses that cause VHFs are only found in specific areas of Africa, South America and Asia, so one key to prevention is avoiding places where these viruses exist. Making sure that all vaccines are up to date before traveling to those areas would also aid in the prevention of contracting one of these fevers.
Use of insect repellent and protective clothing when working outside are also recommended. People charged with slaughter of infected animals or working directly with sick patients obviously need to take special care.
Constant hand washing and bathing are the first and best line of defense. Other methods of prevention would include those same protocols that protect people from more common viral infections. Abstaining from unprotected sexual contact is an example, as is avoidance of other high risk behaviors such as sharing intravenous needles or drinking after an infected person.