Lassa fever, also known as Lassa hemorrhagic fever, is a type of viral hemorrhagic fever caused by the Lassa virus. Many of those infected by the virus do not develop symptoms. When symptoms occur they typically include fever, weakness, headaches, vomiting, and muscle pains. Less commonly there may be bleeding from the mouth or gastrointestinal tract. The risk of death once infected is about one percent and frequently occurs within two weeks of the onset of symptoms. Of those who survive, about a quarter have hearing loss, which improves within three months in about half of these cases.
Dengue fever is a mosquito-borne disease caused by dengue virus, prevalent in tropical and subtropical areas. It is frequently asymptomatic; if symptoms appear they typically begin 3 to 14 days after infection. These may include a high fever, headache, vomiting, muscle and joint pains, and a characteristic skin itching and skin rash. Recovery generally takes two to seven days. In a small proportion of cases, the disease develops into severe dengue with bleeding, low levels of blood platelets, blood plasma leakage, and dangerously low blood pressure.
Marburg virus disease (MVD), formerly Marburg hemorrhagic fever (MHF) is a viral hemorrhagic fever in human and non-human primates caused by either of the two Marburgviruses: Marburg virus (MARV) and Ravn virus (RAVV). Its clinical symptoms are very similar to those of Ebola virus disease (EVD).
Ribavirin, also known as tribavirin, is an antiviral medication used to treat illness caused by respiratory syncytial virus (RSV) and hepatitis C virus (HCV) infections, as well as some viral hemorrhagic fevers. For HCV, it is used in combination with other medications, such as simeprevir, sofosbuvir, peginterferon alfa-2b or peginterferon alfa-2a. It can also be used for viral hemorrhagic fevers—specifically, for Lassa fever, Crimean–Congo hemorrhagic fever, and Hantavirus infections. Ribavirin is usually taken orally or inhaled. Despite widespread usage, it has faced scrutiny in the 21st century because of lack of proven efficacy in treating viral infections for which it has been prescribed in the past.
Filoviridae is a family of single-stranded negative-sense RNA viruses in the order Mononegavirales. Two members of the family that are commonly known are Ebola virus and Marburg virus. Both viruses, and some of their lesser known relatives, cause severe disease in humans and nonhuman primates in the form of viral hemorrhagic fevers.
The genus Ebolavirus is a virological taxon included in the family Filoviridae, order Mononegavirales. The members of this genus are called ebolaviruses, and encode their genome in the form of single-stranded negative-sense RNA. The six known virus species are named for the region where each was originally identified: Bundibugyo ebolavirus, Reston ebolavirus, Sudan ebolavirus, Taï Forest ebolavirus, Zaire ebolavirus, and Bombali ebolavirus. The last is the most recent species to be named and was isolated from Angolan free-tailed bats in Sierra Leone. Each species of the genus Ebolavirus has one member virus, and four of these cause Ebola virus disease (EVD) in humans, a type of hemorrhagic fever having a very high case fatality rate. The Reston virus has caused EVD in other primates. Zaire ebolavirus has the highest mortality rate of the ebolaviruses and is responsible for the largest number of outbreaks of the six known species of the genus, including the 1976 Zaire outbreak and the outbreak with the most deaths (2014).
An arenavirus is a bi- or trisegmented ambisense RNA virus that is a member of the family Arenaviridae. These viruses infect rodents and occasionally humans. A class of novel, highly divergent arenaviruses, properly known as reptarenaviruses, have also been discovered which infect snakes to produce inclusion body disease, mostly in boa constrictors. At least eight arenaviruses are known to cause human disease. The diseases derived from arenaviruses range in severity. Aseptic meningitis, a severe human disease that causes inflammation covering the brain and spinal cord, can arise from the lymphocytic choriomeningitis virus. Hemorrhagic fever syndromes, including Lassa fever, are derived from infections such as Guanarito virus, Junin virus, Lassa virus, Lujo virus, Machupo virus, Sabia virus, or Whitewater Arroyo virus. Because of the epidemiological association with rodents, some arenaviruses and bunyaviruses are designated as roboviruses.
Venezuelan hemorrhagic fever (VHF) is a zoonotic human illness first identified in 1989. The disease is most prevalent in several rural areas of central Venezuela and is caused by Guanarito mammarenavirus (GTOV) which belongs to the Arenaviridae family. The short-tailed cane mouse is the main host for GTOV which is spread mostly by inhalation of aerosolized droplets of saliva, respiratory secretions, urine, or blood from infected rodents. Person-to-person spread is possible, but uncommon.
Crimean–Congo hemorrhagic fever (CCHF) is a viral disease. Symptoms of CCHF may include fever, muscle pains, headache, vomiting due to loss of net saline of basal cells, diarrhea, and bleeding into the skin. Onset of symptoms is less than two weeks following exposure. Complications may include liver failure. Survivors generally recover around two weeks after onset.
Chapare mammarenavirus or Chapare virus is a virus from the family Arenaviridae which causes a hemorrhagic fever in humans known as Chapare hemorrhagic fever. It was first described after an outbreak of a novel zoonotic mammarenavirus infection occurred in the village of Samuzabeti, Chapare Province, Bolivia, in January 2003. A small number of people were infected and one person died.
Lujo is a bisegmented RNA virus—a member of the family Arenaviridae—and a known cause of viral hemorrhagic fever (VHF) in humans. Its name was suggested by the Special Pathogens Unit of the National Institute for Communicable Diseases of the National Health Laboratory Service (NICD-NHLS) by using the first two letters of the names of the cities involved in the 2008 outbreak of the disease, Lusaka (Zambia) and Johannesburg. It is the second pathogenic Arenavirus to be described from the African continent—the first being Lassa virus—and since 2012 has been classed as a "Select Agent" under U.S. law.
The species Bundibugyo ebolavirus is the taxonomic home of one virus, Bundibugyo virus (BDBV), that forms filamentous virions and is closely related to the infamous Ebola virus (EBOV). The virus causes severe disease in humans in the form of viral hemorrhagic fever and is a Select agent, World Health Organization Risk Group 4 Pathogen, National Institutes of Health/National Institute of Allergy and Infectious Diseases Category A Priority Pathogen, Centers for Disease Control and Prevention Category A Bioterrorism Agent, and is listed as a Biological Agent for Export Control by the Australia Group.
Marburg virus (MARV) is a hemorrhagic fever virus of the Filoviridae family of viruses and a member of the species Marburg marburgvirus, genus Marburgvirus. It causes Marburg virus disease in primates, a form of viral hemorrhagic fever. The World Health Organization (WHO) rates it as a Risk Group 4 Pathogen. In the United States, the National Institute of Allergy and Infectious Diseases ranks it as a Category A Priority Pathogen and the Centers for Disease Control and Prevention lists it as a Category A Bioterrorism Agent. It is also listed as a biological agent for export control by the Australia Group.
Ravn virus is a close relative of Marburg virus (MARV). RAVV causes Marburg virus disease in humans and nonhuman primates, a form of viral hemorrhagic fever. RAVV is a Select agent, World Health Organization Risk Group 4 Pathogen, National Institutes of Health/National Institute of Allergy and Infectious Diseases Category A Priority Pathogen, Centers for Disease Control and Prevention Category A Bioterrorism Agent, and listed as a Biological Agent for Export Control by the Australia Group.
Ebola, also known as Ebola virus disease (EVD) and Ebola hemorrhagic fever (EHF), is a viral hemorrhagic fever in humans and other primates, caused by ebolaviruses. Symptoms typically start anywhere between two days and three weeks after infection. The first symptoms are usually fever, sore throat, muscle pain, and headaches. These are usually followed by vomiting, diarrhoea, rash and decreased liver and kidney function, at which point some people begin to bleed both internally and externally. It kills between 25% and 90% of those infected – about 50% on average. Death is often due to shock from fluid loss, and typically occurs between six and 16 days after the first symptoms appear. Early treatment of symptoms increases the survival rate considerably compared to late start. An Ebola vaccine was approved by the US FDA in December 2019.
Orthoebolavirus zairense or Zaire ebolavirus, more commonly known as Ebola virus, is one of six known species within the genus Ebolavirus. Four of the six known ebolaviruses, including EBOV, cause a severe and often fatal hemorrhagic fever in humans and other mammals, known as Ebola virus disease (EVD). Ebola virus has caused the majority of human deaths from EVD, and was the cause of the 2013–2016 epidemic in western Africa, which resulted in at least 28,646 suspected cases and 11,323 confirmed deaths.
FGI-106 is a broad-spectrum antiviral drug developed as a potential treatment for enveloped RNA viruses, in particular viral hemorrhagic fevers from the bunyavirus, flavivirus and filovirus families. It acts as an inhibitor which blocks viral entry into host cells. In animal tests FGI-106 shows both prophylactic and curative action against a range of deadly viruses for which few existing treatments are available, including the bunyaviruses hantavirus, Rift Valley fever virus and Crimean-Congo hemorrhagic fever virus, the flavivirus dengue virus, and the filoviruses Ebola virus and Marburg virus.
Viral hemorrhagic fevers (VHFs) are a diverse group of diseases. Prevention methods are very similar for the different viruses. The vast majority of the information in this article is from the document "Infection Control for Viral Hemorrhagic Fevers in the African Health Care Setting", which was published in December 1998. It was prepared by the Centers for Disease Control and Prevention (CDC) (part of the national government in the United States of America) and the World Health Organization (WHO) (a non-governmental organization).
The 1967 Marburg virus disease outbreak was the first recorded outbreak of Marburg virus disease. It started in early August 1967 when 30 people became ill in the West German towns of Marburg and Frankfurt and later two in Belgrade, Yugoslavia. The infections were traced back to three laboratories in the separate locations which received a shared shipment of infected African green monkeys. The outbreak involved 25 primary Marburg virus infections and seven deaths, and six non-lethal secondary cases.
