The Ebola Virus: What You Need to Know

The Ebola virus has been in the news a lot lately, but many people still don't know what it is or how it spreads. In this blog post, we will discuss the basics of the Ebola virus: what it is, how it is spread, and the symptoms. The Ebola virus is a virus that causes hemorrhagic fever, which is a severe and often fatal illness. The Ebola virus is spread through contact with the blood or body fluids of an infected animal, such as a monkey, chimpanzee, or bat. It can also be spread to humans through contact with the blood or body fluids of an infected person.

'Zaire ebolavirus' commonly known as 'Ebola virus', is one of six recognized species in the genus Ebolavirus. EBOV, along with four of the six known ebolaviruses, including Sudan ebolavirus, causes a severe and often deadly hemorrhagic fever in humans and other mammals known as Ebola virus disease (EVD). There are five known Ebola virus species, four of which have been shown to infect people: Zaire ebolavirus (Ebola virus); Sudan ebolavirus (Sudan ebolavirus); Taï Forest virus (Taâ Forest ebolavirus, previously Côte d'Ivoire ebolavirus); and Bundibugyo virus.

• The ERK Mitogen-Activated Protein Kinase Pathway Contributes to Ebola Virus Glycoprotein-Induced Cytotoxicity.
• It's possible that a heightened immune response can be found in the levels of a few cytokines, such as IL-1RA, IL-6, and ITAC, which rose late during infection but then decreased again during convalescence, suggesting an effective immunological response throughout ebolavirus infection.

Bats, particularly fruit bats, are considered the natural reservoir of Ebola virus and are mostly transmitted between people via bodily fluids.

Particles are usually spherical (although some can be oblong or ovoid) and have a viral envelope, matrix, and nucleocapsid components.The overall cylinders are usually 80 nm in diameter, and the viral-encoded glycoprotein (GP) that projects as 7–10 nm long spikes from its lipid bilayer surface is around 80 nm in length.

There have been more Zaire ebolavirus infections than any other ebolavirus. The first case was reported on August 26, 1976, in Yambuku.

Genome of Zaire Ebola virus

One molecule of linear, single-stranded, negative-sense RNA (18,959 to 18,961 nucleotides) is contained in each virion. The 3′ extremity is nonpolyadenylated, and the 5′ end is not phosphorylated. This viral genome codes for seven structural proteins and one non-structural protein. The gene arrangement is 3′ – leader – NP – VP35 – VP40 – GP/sGP -VP30 -VP24 -L. The leader and the trailer are non-transcribed sections of DNA that transmit critical signals to control transcription, replication, and packaging of viral genomes into new virions. Ebola virus rapidly changes in both a person and in the reservoir of the local human population, with two known variants. The observed mutation rate of 2.0 x 10-3 substitutions per site per year is comparable to that of seasonal influenza.

Ebola virus related products

Replication of Ebola virus disease

Viruses such as Ebola, which are acellular, do not replicate via any sort of cell division; instead, they rely on a combination of host- and viral-encoded enzymes along with host cell components to produce numerous copies of themselves. In the host cell, these molecules then self-assemble into viral macromolecular structures. The glycoprotein (GP) surface peplomer and endocytosis are used by the virus to attach to host receptors and enter macropinosomes in the host cell. After penetration by the virus, the viral membrane joins with the vesicle membrane, and the nucleocapsid is released into the cytoplasm.The viral genome is encapsidated and the 3' portion of the RNA is synthesized (3'-5') using encapsidated, negative-sense genomic ssRNA as a template. The mRNA is further translated into individual viral proteins using the host cell's ribosomes, tRNA molecules.

Transmission of Ebola virus disease

• The virus spreads through direct contact (such as through broken skin or mucous membranes in the eyes, nose, or mouth)
• The virus can survive for a long time in porous objects — such as needles and syringes, or on clothes, belongings (such as gloves) that come into contact with the body fluids of someone who is sick with or has died from Ebola virus disease.
• Objects (such as clothes, bedding, needles, and medical equipment) contaminated with body fluids from a person who is sick with or has died from EVD.
• The virus can live in the bodily fluids of a person who has recovered from EVD for months or years, even if they don't have any obvious symptoms of disease. There is no evidence that Ebola can be spread through sex or other contact with vaginal fluids from a woman who has had Ebola.

Symptoms of Ebola virus disease

Symptoms of the Ebola virus include fever, headache, joint and muscle pain, diarrhea, vomiting, stomach pain, and lack of appetite. Symptoms typically appear within two to 21 days after exposure to the virus, with an average of 8 to 10 days. However, some people may not develop symptoms for several months. The illness generally follows this pattern: "dry" symptoms (such as fever, aches and pains, and tiredness) initially, followed by "wet" symptoms (such as diarrhea and vomiting) as the person becomes sicker.

The following are some of the most common symptoms and signs of Ebola:

• Headache, nausea, and stomach upset are all common in pregnancy. The most severe pains include arthritis and muscular or joint aches.
• Abdominal discomfort, diarrhea, and vomiting are some of the gastrointestinal symptoms that may occur.
• Unexplained hemorrhaging, bleeding or bruising
• Fever
• Weakness and fatigue
• Sore throat
• Loss of appetite

Influenza (flu), malaria, and typhoid fever are just a few of the many illnesses that may have similar symptoms to EVD.

Diagnosis of Ebola virus disease

Polymerase chain reaction (PCR) is one of the most commonly used diagnostic methods because of its ability to detect low levels of Ebola virus. PCR methods can detect the presence of a few virus particles in small amounts of blood, but the ability to detect the virus increases as the amount of virus increases during an active infection.

Treatment for Ebola virus disease

• There is no specific treatment for the Ebola virus, but there are some things that can be done to help manage the symptoms and improve the chances of survival. Treatment includes providing fluids and electrolytes, maintaining oxygen levels, and treating any other infections that may occur. If you think you or someone you know may have been exposed to the Ebola virus, it's important to seek medical attention immediately. Early diagnosis and treatment is critical for survival.
• There are two drugs approved for the treatment of Ebola. Inmazeb drug is a combination of three monoclonal antibodies, the first one to be authorized in October 2020. Ebanga drug is a single monoclonal antibody that was licensed in December 2020.
• Overall survival was much higher for patients receiving either of the two treatments that are now approved by the FDA.

Vaccine for Ebola virus disease

• The VSV-EBOV vaccine has been found to be 70–100% effective in preventing Ebola infection, making it the first vaccination against the disease. In December 2019, the United States Food and Drug Administration gave approval for a vaccine against ZIKV, which is known as VSV-EBOV.
• The rVSV-ZEBOV vaccine has been found to be safe and protective against only the Zaire ebolavirus strain of Ebola virus.
• Although the Ebola virus is a serious disease, it is not easily transferred from person to person. With early detection and appropriate therapy, the chances of survival are considerably higher.

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