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. [1] For past and current Ebola epidemics, treatment has been primarily supportive in nature. [2]
As of August 2023 [update] , treatment known as atoltivimab/maftivimab/odesivimab and experimental ansuvimab were found to be 90% effective. [3] [4] [5] [6]
In October 2020, the U.S. Food and Drug Administration (FDA) approved atoltivimab/maftivimab/odesivimab with an indication for the treatment of infection caused by Zaire ebolavirus. [7]
Articles related to the |
Western African Ebola virus epidemic |
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Overview |
Nations with widespread cases |
Other affected nations |
Other outbreaks |
In March 2014, the World Health Organization (WHO) reported a major Ebola outbreak in Guinea, a western African nation. [8] The disease then rapidly spread to the neighboring countries of Liberia and Sierra Leone. The 2014 West African Ebola outbreak is the largest Ebola outbreak ever documented, and the first recorded in the region. [8]
The director of the US National Institute of Allergy and Infectious Diseases (NIAID) has stated that the scientific community is still in the early stages of understanding how infection with the Ebola virus can be treated and prevented. [9] The unavailability of treatments in the most-affected regions has spurred controversy, with some calling for experimental drugs to be made more widely available in Africa on a humanitarian basis, and others warning that making unproven drugs widely available would be unethical, especially in light of past experimentation conducted in developing countries by Western drug companies. [10] [11] As a result of the controversy, on 12 August an expert panel of the WHO endorsed the use of interventions with as-yet-unknown effects for both treatment and prevention of Ebola, and also said that deciding which treatments should be used and how to distribute them equitably were matters that needed further discussion. [12]
Conventional trials to study efficacy by exposure of humans to the pathogen are obviously not feasible in this case. For such situations, the Food and Drug Administration (FDA) has established the "animal efficacy rule" allowing limited licensure to be approved on the basis of animal model studies that replicate human disease, combined with evidence of safety. A number of experimental treatments are being considered for use in the context of this outbreak, and are currently or will soon undergo clinical trials. [13] A distributed computing project, Outsmart Ebola Together, has been launched by World Community Grid in collaboration with the Scripps Research Institute to help find chemical compounds to fight the disease. It uses the idle processing capacity of volunteers' computers and tablets. [14]
The centre for epidemic and microbiological research and treatment was constructed in the Guinean Kindia province. The centre was designed and created by RUSAL specialists with the assistance of Rospotrebnadzor scientists (RUSAL has invested $10 million). [15]
The World Health Organization (WHO) has stated that transfusion of whole blood or purified serum from Ebola survivors has the greatest potential to be implemented immediately, and has issued an interim guideline for this therapy. [50] A study in Sierra Leone started in November 2014, and preliminary results show an 80 percent survival rate. [51] Trials in Liberia and Guinea started in January 2015, with funding from the Gates Foundation. [52] Blood transfusions were also used in a 1995 outbreak in the Democratic Republic of the Congo, and 7 out of 8 patients survived. [53]
Ribavirin is also known to be ineffective against ebolaviruses despite its effectiveness against other viral hemorrhagic fevers such as Lassa fever. [54] Interferon therapies have been tried as a form of treatment for EVD, but were found to be ineffective. [55]
One issue which hinders control of Ebola is that diagnostic tests that are currently available require specialised equipment and highly trained personnel. Since there are few suitable testing centres in West Africa, this leads to delay in diagnosis. In December, a conference in Geneva will aim to work out which diagnostic tools could identify Ebola reliably and more quickly. The meeting, convened by the WHO and the non-profit Foundation for Innovative New Diagnostics, seeks to identify tests that can be used by untrained staff, do not require electricity or can run on batteries or solar power and use reagents that can withstand temperatures of 40 °C (104 °F). [56]
As of February 2015 [update] , a number of diagnostic tests are under trial:
The Hemopurifier is a single-use disposable biological cartridge designed for use with dialysis machines and other blood circulatory pumps. It is a method for removal of viruses from blood by lectin affinity hemodialysis which embodies reducing viral loads in the blood of individuals infected with a virus. [62] During October 2014, the Hemopurifier was used as an adjunct in the treatment of a patient with Ebola, who then recovered. [63] The FDA subsequently approved the device for testing in up to 20 infected Ebola cases in the United States. [64]
Hepatitis C is an infectious disease caused by the hepatitis C virus (HCV) that primarily affects the liver; it is a type of viral hepatitis. During the initial infection period, people often have mild or no symptoms. Early symptoms can include fever, dark urine, abdominal pain, and yellow tinged skin. The virus persists in the liver, becoming chronic, in about 70% of those initially infected. Early on, chronic infection typically has no symptoms. Over many years however, it often leads to liver disease and occasionally cirrhosis. In some cases, those with cirrhosis will develop serious complications such as liver failure, liver cancer, or dilated blood vessels in the esophagus and stomach.
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.
Genital herpes is a herpes infection of the genitals caused by the herpes simplex virus (HSV). Most people either have no or mild symptoms and thus do not know they are infected. When symptoms do occur, they typically include small blisters that break open to form painful ulcers. Flu-like symptoms, such as fever, aching, or swollen lymph nodes, may also occur. Onset is typically around 4 days after exposure with symptoms lasting up to 4 weeks. Once infected further outbreaks may occur but are generally milder.
Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) co-infection is a multi-faceted, chronic condition that significantly impacts public health. According to the World Health Organization (WHO), 2 to 15% of those infected with HIV are also affected by HCV, increasing their risk of morbidity and mortality due to accelerated liver disease. The burden of co-infection is especially high in certain high-risk groups, such as intravenous drug users and men who have sex with men. These individuals who are HIV-positive are commonly co-infected with HCV due to shared routes of transmission including, but not limited to, exposure to HIV-positive blood, sexual intercourse, and passage of the Hepatitis C virus from mother to infant during childbirth.
Herpes simplex, often known simply as herpes, is a viral infection caused by the herpes simplex virus. Herpes infections are categorized by the area of the body that is infected. The two major types of herpes are oral herpes and genital herpes, though other forms also exist.
A neutralizing antibody (NAb) is an antibody that defends a cell from a pathogen or infectious particle by neutralizing any effect it has biologically. Neutralization renders the particle no longer infectious or pathogenic. Neutralizing antibodies are part of the humoral response of the adaptive immune system against viruses, bacteria and microbial toxin. By binding specifically to surface structures (antigen) on an infectious particle, neutralizing antibodies prevent the particle from interacting with its host cells it might infect and destroy.
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.
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.
Brincidofovir, sold under the brand name Tembexa, is an antiviral drug used to treat smallpox. Brincidofovir is a prodrug of cidofovir. Conjugated to a lipid, the compound is designed to release cidofovir intracellularly, allowing for higher intracellular and lower plasma concentrations of cidofovir, effectively increasing its activity against dsDNA viruses, as well as oral bioavailability.
ZMapp is an experimental biopharmaceutical drug comprising three chimeric monoclonal antibodies under development as a treatment for Ebola virus disease. Two of the three components were originally developed at the Public Health Agency of Canada's National Microbiology Laboratory (NML), and the third at the U.S. Army Medical Research Institute of Infectious Diseases; the cocktail was optimized by Gary Kobinger, a research scientist at the NML and underwent further development under license by Mapp Biopharmaceutical. ZMapp was first used on humans during the Western African Ebola virus epidemic, having only been previously tested on animals and not yet subjected to a randomized controlled trial. The National Institutes of Health (NIH) ran a clinical trial starting in January 2015 with subjects from Sierra Leone, Guinea, and Liberia aiming to enroll 200 people, but the epidemic waned and the trial closed early, leaving it too statistically underpowered to give a meaningful result about whether ZMapp worked.
TKM-Ebola was an experimental antiviral drug for Ebola disease that was developed by Arbutus Biopharma in Vancouver, Canada. The drug candidate was formerly known as Ebola-SNALP.
Ebola vaccines are vaccines either approved or in development to prevent Ebola. As of 2022, there are only vaccines against the Zaire ebolavirus. The first vaccine to be approved in the United States was rVSV-ZEBOV in December 2019. It had been used extensively in the Kivu Ebola epidemic under a compassionate use protocol. During the early 21st century, several vaccine candidates displayed efficacy to protect nonhuman primates against lethal infection.
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.
In 2014, Ebola virus disease in Spain occurred due to two patients with cases of the disease contracted during the Ebola virus epidemic in West Africa; they were medically evacuated. A failure in infection control in the treatment of the second patient led to an isolated infection of Ebola virus disease in a health worker in Spain itself. The health worker survived her Ebola infection, and has since been declared infection-free.
The 2018 Équateur province Ebola outbreak occurred in the north-west of the Democratic Republic of the Congo (DRC) from May to July 2018. It was contained entirely within Équateur province, and was the first time that vaccination with the rVSV-ZEBOV Ebola vaccine had been attempted in the early stages of an Ebola outbreak, with a total of 3,481 people vaccinated. It was the ninth recorded Ebola outbreak in the DRC.
Ansuvimab, sold under the brand name Ebanga, is a monoclonal antibody medication for the treatment of Zaire ebolavirus (Ebolavirus) infection.
COVID-19 drug development is the research process to develop preventative therapeutic prescription drugs that would alleviate the severity of coronavirus disease 2019 (COVID-19). From early 2020 through 2021, several hundred drug companies, biotechnology firms, university research groups, and health organizations were developing therapeutic candidates for COVID-19 disease in various stages of preclinical or clinical research, with 419 potential COVID-19 drugs in clinical trials, as of April 2021.
Convalescent plasma is the blood plasma collected from a survivor of an infectious disease. This plasma contains antibodies specific to a pathogen and can be used therapeutically by providing passive immunity when transfusing it to a newly infected patient with the same condition. Convalescent plasma can be transfused as it has been collected or become the source material for hyperimmune serum or anti-pathogen monoclonal antibodies; the latter consists exclusively of IgG, while convalescent plasma also includes IgA and IgM. Collection is typically achieved by apheresis, but in low-to-middle income countries, the treatment can be administered as convalescent whole blood.
Atoltivimab/maftivimab/odesivimab, sold under the brand name Inmazeb, is a fixed-dose combination of three monoclonal antibodies for the treatment of Zaire ebolavirus. It contains atoltivimab, maftivimab, and odesivimab-ebgn and was developed by Regeneron Pharmaceuticals.
Gary P. Kobinger is a Canadian immunologist and virologist who is currently the director at the Galveston National Laboratory at the University of Texas. He has held previous professorships at Université Laval, the University of Manitoba, and the University of Pennsylvania. Additionally, he was the chief of the Special Pathogens Unit at the National Microbiology Laboratory (NML) of the Public Health Agency of Canada (PHAC) in Winnipeg, Manitoba, for eight years. Kobinger is known for his critical role in the development of both an effective Ebola vaccine and treatment. His work focuses on the development and evaluation of new vaccine platforms and immunological treatments against emerging and re-emerging viruses that are dangerous to human health.
The two new therapies were among four that were tested in a trial that has enrolled almost 700 patients since November. The two worked so well that a committee meeting on Friday to look at preliminary results in the first 499 patients immediately recommended that the other two treatments, ZMapp, made by Mapp Biopharmaceutical, and remdesivir, made by Gilead Sciences, be stopped. All patients will now be offered either the Regeneron or the Biotherapeutics drug.