What is Ebola
. The Ebola virus disease (EVD), formerly known as Ebola hemorrhagic fever is a severe condition caused by a virus from the Filoviridae family. Known to be a condition that is transmitted from animals to humans, this virus spreads through direct contact with the bodily fluids of an infected person or animal.
. Ebola is introduced into the human population through close contact with the blood, secretions, organs or other bodily fluids of infected animals. In Africa, infection has been documented through the handling of infected chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines found ill or dead or in the rainforest.Ebola then spreads in the community through human to human transmission, with infection resulting from direct cont
Signs and symptoms
. EVD is a severe acute viral illness often characterized by the sudden onset of fever, intense weakness, muscle pain, headache and sore throat. This is followed by vomiting, diarrhoea, rash, impaired kidney and liver function, and in some cases, both internal and external bleeding. Laboratory findings include low white blood cell and platelet counts and elevated liver enzymes.People are infectious as long as their blood and secretions contain the
. Other diseases that should be ruled out before a diagnosis of EVD can be made include malaria, typhoid fever, shigellosis, cholera, leptospirosis, plague, rickettsiosis, relapsing fever, meningitis, hepatitis and other viral haemorrhagic fevers.Ebola virus infections can be diagnosed definitively in a laboratory through several types of testsantibody capture enzyme linked immunosorbent assay (ELISA) antigen detection testsserum neutralization
Vaccine and treatment
. No licensed vaccine for EVD is available. Several vaccines are being tested, but none are available for clinical use.Severely ill patients require intensive supportive care. Patients are frequently dehydrated and require oral rehydration with solutions containing electrolytes or intravenous fluids.No specific treatment is available. New drug therapies are being evaluated.
Natural host of Ebola virus
. In Africa, fruit bats, particularly species of the genera Hypsignathus monstrosus, Epomops franqueti and Myonycteris torquata, are considered possible natural hosts for Ebola virus. As a result, the geographic distribution of Ebolaviruses may overlap with the range of the fruit bats.
Ebola virus in animals
. Although non human primates have been a source of infection for humans, they are not thought to be the reservoir but rather an accidental host like human beings. Since 1994, Ebola outbreaks from the EBOV and TAFV species have been observed in chimpanzees and gorillas.RESTV has caused severe EVD outbreaks in macaque monkeys (Macaca fascicularis) farmed in Philippines and detected in monkeys imported into the ?USA in 1989, 1990 and 1996, and in mo
Controlling infection in health care settings
. Human to human transmission of the Ebola virus is primarily associated with direct or indirect contact with blood and body fluids. Transmission to health care workers has been reported when appropriate infection control measures have not been observed.It is not always possible to identify patients with EBV early because initial symptoms may be non specific. For this reason, it is important that health care workers apply standard precautions cons
. WHO provides expertise and documentation to support disease investigation and control.Recommendations for infection control while providing care to patients with suspected or confirmed Ebola haemorrhagic fever are provided in Interim infection control recommendations for care of patients with suspected or confirmed Filovirus (Ebola, Marburg) haemorrhagic fever, March 2008. This document is currently being updated.WHO has created an aide memoire
Transmission from animals to humans
. Experts suspect that both viruses are transmitted to humans through an infected animals bodily fluids. Examples includeBlood. Butchering or eating infected animals can spread the viruses. Scientists who have operated on infected animals as part of their research have also contracted the virus.Waste products. Tourists in certain African caves and some underground mine workers have been infected with the Marburg virus, possibly through contact with
Transmission from person to person
. Infected people typically dont become contagious until they develop symptoms. Family members are often infected as they care for sick relatives or prepare the dead for burial.Medical personnel can be infected if they dont use protective gear, such as surgical masks and gloves. Medical centers in Africa are often so poor that they must reuse needles and syringes. Some of the worst Ebola epidemics have occurred because contaminated injection equipm
Preparing for your appointment
. The possibility of contracting Ebola or Marburg virus is extremely low unless youve had direct contact with the body fluids of an infected person or animal.If you think that you or a family member may have been exposed to one of the viruses, call your doctor or go to the nearest emergency room immediately. If youre not referred to an infectious disease specialist, ask to see one.If youre from the United States and traveling or working abroad, the
What you can do
. Before your appointment, to help your doctor find the cause of your symptoms, write a list that answers the following questionsWhat symptoms do you have When did they start Have you recently traveled in Africa If so, what part If you were recently in Africa, did you hunt or eat monkeys Did you recently visit caves or underground mines in Africa Are you employed in a lab that uses monkeys from Africa or the Philippines in research?If possible, ta
Tests and diagnosis
. Ebola and Marburg hemorrhagic fevers are difficult to diagnose because early signs and symptoms resemble those of other diseases, such as typhoid and malaria. If doctors suspect you have Ebola or Marburg viruses, they use blood tests to quickly identify the virus, includingEnzyme linked immunosorbent assay (ELISA)Reverse transcriptase polymerase chain reaction (PCR)The Centers for Disease Control and Prevention monitors the United States for cond
. According to the WHO reports, on an average, 80% of the people infected with this virus do die. Their death is usually due to a drop in their blood pressure and failure of organs.
. According to Dr Ratan, There arent any vaccinations available as of now, so basic hygiene is of importance and a must be followed in order to prevent the onset of the condition. Simple activities like washing your hands well, drinking water from a clean source, maintaining general hygiene and cooking your meat well, can all serve as precautionary measures. Apart from that people should avoid crowded places, or those that are known to have an outb
. Zaire ebolavirus is pronounced. Strictly speaking, the pronunciation of Ebola virus should be distinct from that of the genus level taxonomic designation ebolavirus Ebolavirus ebolavirus, as Ebola is named for the tributary of the Congo River that is pronounced
. Ebola virus was first introduced as a possible new strain of Marburg virus in 1977 by two different research teams. At the same time, a third team introduced the name Ebola virus.In 2000, the virus name was changed to Zaire Ebola virus, and in 2002 to Zaire ebolavirus.However, most scientific articles continued to refer to Ebola virus or used the terms Ebola virus and Zaire ebolavirus in parallel. Consequently, in 2010, the name Ebola virus was r
. Ebolavirus is a zoonotic pathogen. Intermediary hosts have been reported to be various species of fruit bats throughout central and sub Saharan Africa, but infection in bats has not been proven yet. End hosts are humans and great apes, infected through bat contact or through other end hosts. Pigs on the Philippine islands have been reported to be infected with Restonvirus, so other interim or amplifying hosts may exist.
. Bats are considered the most likely natural reservoir of the Ebola virus (EBOV); plants, arthropods, and birds have also been considered. Bats were known to reside in the cotton factory in which the first cases for the 1976 and 1979 outbreaks were employed, and they have also been implicated in Marburg virus infections in 1975 and 1980.Of 24 plant species and 19 vertebrate species experimentally inoculated with EBOV, only bats became infected. Th
. The ebolavirus life cycle begins with virion attachment to specific cell surface receptors, followed by fusion of the virion envelope with cellular membranes and the concomitant release of the virus nucleocapsid into the cytosol. The viral RNA polymerase, encoded by the L gene, partially uncoats the nucleocapsid and transcribes the genes into positive strand mRNAs, which are then translated into structural and nonstructural proteins. Ebolavirus R
. The genera Ebolavirus and Marburgvirus were originally classified as the species of the now obsolete Filovirus genus. In March 1998, the Vertebrate Virus Subcommittee proposed in the International Committee on Taxonomy of Viruses (ICTV) to change the Filovirus genus to the Filoviridae family with two specific genera: Ebola like viruses and Marburg like viruses. This proposal was implemented in Washington, DC, on April 2001 and in Paris on July 20
. The symptoms of EVD are similar to those of Marburg virus disease.It can also easily be confused with many other diseases common in Equatorial Africa such as other viral hemorrhagic fevers, falciparum malaria, typhoid fever, shigellosis, rickettsial diseases such as typhus, cholera, gram negative septicemia, borreliosis such as relapsing fever or EHEC enteritis. Other infectious diseases that should be included in the differential diagnosis inclu
. Ebola viruses are contagious, with prevention predominantly involving behavior changes, proper full body personal protective equipment, and disinfection. Techniques to avoid infection involve not contacting infected blood or secretions, including from those who are dead. This involves suspecting and diagnosing the disease early and using standard precautions for all patients in the healthcare setting. Recommended measures when caring for those wh
. Quarantine, also known as enforced isolation, is usually effective in decreasing spread.Governments often quarantine areas where the disease is occurring or individuals who may be infected. In the United States the law allows quarantine of those infected with Ebola. The lack of roads and transportation may help slow the disease in Africa. During the 2014 outbreak Liberia closed schools.
. No vaccine is currently available for humans. The most promising candidates are DNA vaccines or vaccines derived from adenoviruses, vesicular stomatitis Indiana virus (VSIV) or filovirus like particles (VLPs) because these candidates could protect nonhuman primates from ebolavirus induced disease. DNA vaccines, adenovirus based vaccines, and VSIV based vaccines have entered clinical trials. Vaccines have protected nonhuman primates. Immunization
. No ebolavirus specific treatment exists. Treatment is primarily supportive in nature and includes minimizing invasive procedures, balancing fluids and electrolytes to counter dehydration, administration of anticoagulants early in infection to prevent or control disseminated intravascular coagulation, administration of procoagulants late in infection to control bleeding, maintaining oxygen levels, pain management, and the use of medications to tre
. Favipiravir looks like it may be useful in a mouse model of the disease. Estrogen receptor drugs used to treat infertility and breast cancer (clomiphene and toremifene) inhibit the progress of Ebola virus in infected mice. Ninety percent of the mice treated with clomiphene and fifty percent of those treated with toremifene survived the tests. Given their oral availability and history of human use, these drugs would be candidates for treating Ebol