Marburg virus disease 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 RSV infection, hepatitis C and some viral hemorrhagic fevers. For hepatitis C, it is used in combination with other medications such as simeprevir, sofosbuvir, peginterferon alfa-2b or peginterferon alfa-2a. Among the viral hemorrhagic fevers it is used for Lassa fever, Crimean–Congo hemorrhagic fever, and Hantavirus infection but should not be used for Ebola or Marburg infections. Ribavirin is taken by mouth or inhaled.
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).
Viral hemorrhagic fevers (VHFs) are a diverse group of animal and human illnesses. VHFs may be caused by five distinct families of RNA viruses: the families Filoviridae, Flaviviridae, Rhabdoviridae, and several member families of the Bunyavirales order such as Arenaviridae, and Hantaviridae. All types of VHF are characterized by fever and bleeding disorders and all can progress to high fever, shock and death in many cases. Some of the VHF agents cause relatively mild illnesses, such as the Scandinavian nephropathia epidemica, while others, such as Ebola virus, can cause severe, life-threatening disease.
Nucleoside analogues are structural analogues of a nucleoside, which normally contain a nucleobase and a sugar. Nucleotide analogues are analogues of a nucleotide, which normally has one to three phosphates linked to a nucleoside. Both types of compounds can deviate from what they mimick in a number of ways, as changes can be made to any of the constituent parts. They are related to nucleic acid analogues.
Umifenovir, sold under the brand name Arbidol, is an antiviral medication for the treatment of influenza and COVID infections used in Russia and China. The drug is manufactured by Pharmstandard. It is not approved by the U.S. Food and Drug Administration (FDA) for the treatment or prevention of influenza.
FGI-104 is the name of an experimental broad-spectrum antiviral drug, with activity against a range of viruses including hepatitis B, hepatitis C, HIV, Ebola virus, and Venezuelan equine encephalitis virus.
Reston virus (RESTV) is one of six known viruses within the genus Ebolavirus. Reston virus causes Ebola virus disease in non-human primates; unlike the other five ebolaviruses, it is not known to cause disease in humans, but has caused asymptomatic infections. Reston virus was first described in 1990 as a new "strain" of Ebola virus (EBOV). It is the single member of the species Reston ebolavirus, which is included into the genus Ebolavirus, family Filoviridae, order Mononegavirales. Reston virus is named after Reston, Virginia, US, where the virus was first discovered.
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 virus is considered to be extremely dangerous. 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.
3-Deazaneplanocin A is a drug which acts as both a S-adenosylhomocysteine synthesis inhibitor and also a histone methyltransferase EZH2 inhibitor. Studies have shown that it has effects in vitro against a variety of different tumor cell lines.
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.
Favipiravir, sold under the brand name Avigan among others, is an antiviral medication used to treat influenza in Japan. It is also being studied to treat a number of other viral infections, including SARS-CoV-2. Like the experimental antiviral drugs T-1105 and T-1106, it is a pyrazinecarboxamide derivative.
Galidesivir is an antiviral drug, an adenosine analog. It was developed by BioCryst Pharmaceuticals with funding from NIAID, originally intended as a treatment for hepatitis C, but subsequently developed as a potential treatment for deadly filovirus infections such as Ebola virus disease and Marburg virus disease, as well as Zika virus. Currently, galidesivir is under phase 1 human trial in Brazil for coronavirus.
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.
LJ-001 is a broad-spectrum antiviral drug developed as a potential treatment for enveloped viruses. It acts as an inhibitor which blocks viral entry into host cells at a step after virus binding but before virus–cell fusion, and also irreversibly inactivates the virions themselves by generating reactive singlet oxygen molecules which damage the viral membrane. In cell culture tests in vitro, LJ-001 was able to block and disable a wide range of different viruses, including influenza A, filoviruses, poxviruses, arenaviruses, bunyaviruses, paramyxoviruses, flaviviruses, and HIV. Unfortunately LJ-001 itself was unsuitable for further development, as it has poor physiological stability and requires light for its antiviral mechanism to operate. However the discovery of this novel mechanism for blocking virus entry and disabling the virion particles has led to LJ-001 being used as a lead compound to develop a novel family of more effective antiviral drugs with improved properties.
There is a cure for the Ebola virus disease that is currently approved for market the US government has inventory in the Strategic National Stockpile. For past and current Ebola epidemics, treatment has been primarily supportive in nature.
Broad-spectrum antivirals (BSAs) are a class of molecules or compounds, which inhibit the infection of multiple viruses from the same or different virus families. BSAs could be divided into experimental and investigational agents, and approved drugs. BSAs work by inhibiting viral proteins or by targeting host cell factors and processes exploited by different viruses during infection. As of 2021, there are 150 known BSAs in varying stages of development, effective against 78 human viruses. BSAs are potential candidates for treatment of emerging and re-emerging viruses, such as ebola, marburg, and SARS-CoV-2. Many BSAs show antiviral activity against other viruses than originally investigated. Efforts in drug repurposing for SARS-CoV-2 is currently underway. A database of BSAs and viruses they inhibit could be found here.
Endothelial cell tropism or endotheliotropism is a type of tissue tropism or host tropism that characterizes an pathogen's ability to recognize and infect an endothelial cell. Pathogens, such as viruses, can target a specific tissue type or multiple tissue types. Like other cells, the endothelial cell possesses several features that supports a productive viral infection a cell including, cell surface receptors, immune responses, and other virulence factors. Endothelial cells are found in various tissue types such as in the capillaries, veins, and arteries in the human body. As endothelial cells line these blood vessels and critical networks that extend access to various human organ systems, the virus entry into these cells can be detrimental to virus spread across the host system and affect clinical course of disease. Understanding the mechanisms of how viruses attach, enter, and control endothelial functions and host responses inform infectious disease understanding and medical countermeasures.
