Ebola.pptx

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1. EBOLA BSBT 13B | Group-C This Photo by Unknown Author is licensed under CC BY-NC

2. agenda Discovery​ Morphology Modes of Transmission Mechanism of Action Life Cycle Symptoms Diagnosis Treatment 2 EBOLA 2022 This Photo by Unknown Author is licensed under CC BY-SA

3. DISCOVERY Ebola virus disease (EVD), one of the deadliest viral diseases, was discovered in 1976 when two consecutive outbreaks of fatal hemorrhagic fever occurred in different parts of Central Africa. The first outbreak occurred in the Democratic Republic of Congo (formerly Zaire) in a village near the Ebola River, which gave the virus its name. The second outbreak occurred in what is now South Sudan, approximately 500 miles (850 km) away​. 3

4. Initially, public health officials assumed these outbreaks were a single event associated with an infected person who traveled between the two locations. However, scientists later discovered that the two outbreaks were caused by two genetically distinct viruses: Zaire ebolavirus and Sudan ebolavirus. After this discovery, scientists concluded that the virus came from two different sources and spread independently to people in each of the affected areas

5. RECENT OUTBREAKS On July 4, 2022 The Ministry of Health declared the end of the Ebola outbreak in Equateur Province. On August 22, 2022 The Ministry of Health (MOH) in the Democratic Republic of the Congo (DRC) announced an outbreak of Ebola virus disease (EVD) in North Kivu Province. This announcement came after a fatal case was discovered in Beni Health Zone, one of the epicenters of DRC’s 10th outbreak in 2018-2020. 5 EBOLA 20XX

6. MORPHOLOGY Ebola Virus are generally approximately 80 nm in diameter, 970 nm long. They are cylindrical/tubular, and contain viral envelope, matrix, and nucleocapsid components. The virus generally appears in a long, filamentous form, but it can also be “U-shaped,” in the shape of a “6” (the “shepherd’s crook” appearance), or even circular. They have a virally encoded glycoprotein (GP) projecting as 7-10 nm long spikes from its lipid bilayer surface. 6 Presentation Title 20XX

7. Glycoproteins are proteins that contain carbohydrate chains (glycans) covalently attached to their polypeptide side chains, a process known as glycosylation. The glycoprotein GP is the sole resident of the Ebolavirus surface and is responsible for attaching to and entering new host cells. The outer viral envelope of the virion is derived by budding from domains of host cell membrane into which the GP spikes have been inserted during their biosynthesis. This virus belongs to the Filovirus family, and structurally it resembles a length of thread. 7 Presentation Title 20XX

8. MODES OF Transmission • Unsterilized needles. • Sub optical hospital conditions. • Personal contact. • Through blood-to-blood contact. • Human to human transmission. • Reusing needles and blood gloves in hospital. • Ebola is introduced into the human population through close contact with the blood, secretions, organs or other bodily fluids of infected animals. 8

9. Mechanism of Action 1 Every tissue is affected, except bones and muscles. 4 It prevents oxygen to rise tissue. 2 The virus creates blood clots. 5 The virus also destroys connective tissue (affinity with collagen). 3 Clots goes towards internal organs (lungs, Eyeball). 9 EBOLA 222X

10. LIFE CYCLE OF EBOLA 10 EBOLA 2022

11. ATTACHMENT Attachment of Ebola virus to host receptors through GP glycoprotein like DC-SIGN and DC-SIGNR Cellular receptor like HAVCR1(TIM1) binds phosphatidyl serine on virion membrane and a signal is transduced into the cell that trigger the Macropinocytosis program 11 EBOLA 2022 ENTRY OF VIRUS The virion enters the cell by Macropinocytosis In some culture cells, GP glycoprotein can be processed by host Cathepsin L and Cathepsin B into 19kDa GP1. But this processing is not happening in all cells or for all ebolavirus. GP1 interacts with host NPC1, in late macropinosome and promotes Fusion of virus membrane with the vesicle membrane. The ribonucleocapsid is then released into the cytoplasm.

12. VIRUS REPLICATION Once inside the host cell, the virus initiates transcription at the leader end of the genome with the binding of the polymerase complex5. VP30 is an important transcription activation factor for viral genome transcription, while VP24 is an inhibitor to this process. The exact mechanism of VP24-dependent transcription termination is not fully understood, but it seems to be important for converting the virus from its transcriptional or replication active form to one that is geared for virion assembly and exit from host cell. 12 EBOLA 2022

13. VIRUS BUDDING 13 EBOLA 2022 Following replication, the cell loses its connection with other cells as well as attachment to its substrate. Meanwhile, the newly synthesized genomes are packaged into new buds or virions and egresses from the host cell surface with the help of the matrix protein VP40. VP40 interacts with ubiquitin ligase Nedd4 which is a part of human ubiquitination enzyme pathway and links multiple copies of ubiquitin molecules to VP4013. VP40 itself is transported to the host cell plasma membrane using the COPII transport system14. Once in the plasma membrane, the virus moves through lipid rafts where the final assembly and budding of the virions occur, before their final exit from the host cell.

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15. SYMPTOMS 15 EBOLA 2022

16. SYMPTOMS In 40–50% of cases, bleeding from puncture sites and mucous membranes (e.g., gastrointestinal tract, nose, vagina and gums) has been reported. Types of bleeding known to occur with Ebola virus disease include vomiting blood, coughing it up or blood in the stool. Heavy bleeding is rare and is usually confined to the gastrointestinal tract In general, the development of bleeding symptoms often indicates a worse prognosis, and this blood loss can result in death. All people infected show some symptoms of circulatory system involvement, including impaired blood clotting. If the infected person does not recover, death due to multiple organ dysfunction syndrome occurs within 7 to 16 days (usually between days 8 and 9) after first symptoms 16 EBOLA 2022

17. DIAGNOSIS Diagnosing Ebola can be difficult at first since early symptoms, such as fever, are non-specific to Ebola infection. Samples are collected from the patient to be tested to confirm infection. 17 Presentation Title 20XX

18. DIAGNOSIS TESTS 18 EBOLA 2022

19. TREATMENT There's no cure for Ebola, though researchers are working on it. There are two drug treatments which have been approved for treating Ebola. Inmazeb is a mixture of three monoclonal antibodies (atoltivimab, maftivimab, and odesivimab-ebgn). Ebanga is a monoclonal antibody given as an injection. It helps block the virus from the cell receptor, preventing its entry into the cell. Doctors manage the symptoms of Ebola with: Blood transfusions Blood pressure medication Oxygen Fluids and electrolytes 19 EBOLA 2022

20. VACCINES rVSV -ZEBOV vaccine Also known as Ervebo , this vaccine only treats the Zaire strain of the virus. In December 2019, the FDA approved the vaccine for people who qualify for it. You can get the Zaire Ebola vaccine only if you’re 18 or older. Experts don’t recommend it if you’re pregnant and breastfeeding. Experts recommend this vaccine during an Ebola outbreak. Ad26.ZEBOV and MVA-BN- FilO VACCINE Zabdeno and Mvabea respectively, this vaccine is given in two doses. People 1 year or older can get the vaccine. You’ll get Zabdeno as your first vaccine dose. The second-dose Mvabea is given 8 weeks later. For high-risk people like health care workers or volunteers living and working in areas with an Ebola outbreak, if you’ve completed the two doses, you can get a Zabdeno booster shot 4 months after your second dose. 20 EBOLA 2022

21. Thank you Wareesha Azed Talyia Tanveer Hafsa Anis Haleema Saadia Taqdees Zahra Samina​ Bibi Javeria Shafique Shanzay Asad 22 EBOLA 2022 This Photo by Unknown Author is licensed under CC BY-ND