1. Presented by: DR S.D SHEKDE

2. EBOLA VIRUS Presented byDr.S.D.ShekdeJR 2 Guided byDR. V. M.HOLAMBEH.O.D.Assist. ProfessorDept Of Comm. MedicineG.M.C. LATURDate-30/08/14 3. INTRODUCTION Ebola first appeared in 1976 in 2 simultaneousoutbreaks, in Nzara, Sudan, and in Yambuku,Democratic Republic of Congo. The latter was in a village situated near the Ebola River,from which the disease takes its name. Fruit bats of the Pteropodidae family are considered tobe the natural host of the Ebola virus. 4. INTRODUCTION Ebola first appeared in 1976 in 2 simultaneousoutbreaks, in Nzara, Sudan, and in Yambuku,Democratic Republic of Congo. The latter was in a village situated near the Ebola River,from which the disease takes its name. Fruit bats of the Pteropodidae family are considered tobe the natural host of the Ebola virus. 5. VIRUS CLASSIFICATION Genus Ebolavirus is 1 of 3 members of the Filoviridaefamily ( filovirus),along with genus Marburg virus and genus Cuevavirus. Group: Group V (-)ssRNAOrder: MononegaviralesFamily: FiloviridaeGenus:Ebolavirus 6. SPECIES Genus Ebolavirus comprises 5 distinct species: Bundibugyo ebolavirus (BDBV) Zaire ebolavirus (EBOV) Sudan ebolavirus (SUDV) Reston ebolavirus (RESTV) Ta Forest ebolavirus (TAFV).Outbreaksof AFRICA BDBV, EBOV, and SUDV have been associated with large EVDoutbreaks in Africa, whereas RESTV and TAFV have not. The RESTV species, found in Philippines and the PeoplesRepublic of China, can infect humans, but no illness or death inhumans from this species has been reported to date. 7. The Zaire ebolavirus is the most dangerousof the five species of Ebola viruses of theEbolavirus genus which are the causativeagents of Ebola virus disease.(EVD)The virus causes an extremelysevere hemorrhagic fever in humans andother primate. 8. The name Zaire ebolavirus is derived from Zaire,the country (now the Democratic Republic ofCongo) in which the Ebola virus was firstdiscovered) and the taxonomic suffix ebolavirus (which denotes an ebola virus species). 9. VIRION STRUCTURE 10. The EBOV genome is approximately 19 kb in length. Itencodes seven structural proteins: nucleoprotein (NP) polymerase cofactor (VP35), (VP40) GP transcription activator (VP30), VP24 RNA polymerase (L) 11. The tubular Ebola virions are generally 80 nm indiameter and 800 nm long. In the center of theparticle is the viral nucleocapsid which consists of thehelical ssRNA genome wrapped about the NP, VP35,VP30 and L proteins. This structure is then surrounded by an outer viralenvelope derived from the host cell membrane that isstudded with 10 nm long viral glycoprotein (GP)spikes. Between the capsid and envelope are viralproteins VP40 and VP24 . 12. This envelope GP spike is expressed at the cell surface,and is incorporated into the virion to drive viralattachment and membrane fusion. It has also been shown as the crucial factor for Ebolavirus pathogenicity . GP is actually post-translationally cleaved by theproprotein convertase furin to yield disulphide-linkedGP1 and GP2 subunits. 13. GP1 allows for attachment to host cells, while GP2mediates fusion of viral and host membranes. This protein assembles as a trimer of heterodimers onthe viral envelope, and ultimately undergoes anirreversible conformation change to merge the twomembranes 14. Pathophysiology 15. Endothelial cells, mononuclear phagocytes,and hepatocytes are the main targets of infection. Afterinfection, a secreted glycoprotein (sGP) known as the Ebolavirus glycoprotein (GP) is synthesized. Ebola replication overwhelms protein synthesis of infectedcells and host immune defenses. The GP forms a trimeric complex, which binds the virus tothe endothelial cells lining the interior surface of bloodvessels. 16. The sGP forms a dimeric protein that interferes with thesignaling of neutrophils, a type of white blood cell, whichallows the virus to evade the immune system by inhibitingearly steps of neutrophil activation. These white blood cells also serve as carriers to transport thevirus throughout the entire body to places such as the lymphnodes, liver, lungs, and spleen. 17. EPIDEMIOLOGY 18. http://www.cdc.gov/vhf/ebola/resources/distribution-map.html 19. Current Ebola Outbreak in WestAfrica The current (2014) Ebola outbreak is occurring in thefollowing West African countries: Guinea Liberia Sierra Leone Nigeria 20. The virus is transmitted to people from wild animals and spreads in thehuman population through human-to-human transmission. EVD outbreaks occur primarily in remote villages in Central and West Africa,near tropical rainforests.AlvinChew slideshare presentationalvinworks2006@yahoo.com 21. TRANSMISSIONThe virus is spread through directcontact (through broken skin ormucous membranes) withi. sick person's blood or body fluids(urine, saliva, feces, vomit, sweatand semen)ii. objects (such as needles) that havebeen contaminated with infectedbody fluids.iii. Infected animals. 22. Exposure to ebola viruses can occur in healthcaresettings where hospital staff are not wearingappropriate protective equipment, such as masks,gowns, and gloves. Proper cleaning and disposal of instruments, suchas needles and syringes, is also important. 23. TransmissionAnimal tohuman Consumption ofraw meat Contact wit fruitbat, pigs, apes-animalhandlers Animal products(blood, urine andfeces.)Human tohuman Close contactwith infectedpatients Care personnelsof patient Health careworkersPrompt and safeburial of deadbodies.No to AutopsyVirus containedin dead body fora period 4 weeks. 24. Men who have recovered from the illness can stillspread the virus to their partner through their semenfor up to 7 weeks after recovery. Burial ceremonies in which mourners have directcontact with the body of the deceased person haveplayed a role in the transmission of Ebola. 25. Who is most at risk? During an outbreak, those at higher risk of infectionare: Health workers. Family members or others in close contact withinfected people; and Mourners who have direct contact with the bodies ofthe deceased as part of burial ceremonies. 26. Ebola Virus Disease 27. SUDDEN ONSET FEVER SORE THROATINTENSE WEAKNESS MUSCLE PAIN, HEADACHEVOMITTING RASHDIARRHOEA IMPAIRED KIDNEY ANDRENAL FUNCTIONLABLOW WBCLOW PLATELETELEVATEDLIVER ENZYMES. 28. In some cases, both internal and external bleeding. People are infectious as long as their blood andsecretions contain the virus. Ebola virus was isolatedfrom semen 61 days after onset of illness in a man whowas infected in a laboratory. The incubation period, that is, the time interval frominfection with the virus to onset of symptoms, is 2 to 21days. 29. The patient becomes contagious once they begin toshow symptoms. They are not contagious during theincubation period. Ebola virus disease infections can only be confirmedthrough laboratory testing. 30. AlvinChew slideshare presentationalvinworks2006@yahoo.com 31. In some cases, both internal and external bleeding. People are infectious as long as their blood andsecretions contain the virus. Ebola virus was isolatedfrom semen 61 days after onset of illness in a man whowas infected in a laboratory. The incubation period, that is, the time interval frominfection with the virus to onset of symptoms, is 2 to 21days. 32. Person Under Investigation (PUI) A person who has both consistent symptoms and riskfactors as follows: 1) Clinical criteria, which includes fever of greater than38.6 degrees Celsius or 101.5 degrees Fahrenheit, andadditional symptoms such as severe headache, musclepain, vomiting, diarrhea, abdominal pain, orunexplained hemorrhage. 33. 2) Epidemiologic risk factors within thepast 21 days before the onset of symptoms, such ascontact with blood or other body fluids or humanremains of a patient known to have or suspected tohave EVD; residence inor travel toan area where EVDtransmission is active. or direct handling of bats,rodents, or primates from disease-endemic areas. 34. Probable Case A PUI who is a contact of an EVD case with either ahigh or low risk exposure.Confirmed Case A case with laboratory confirmed diagnostic evidenceof ebola virus infection. 35. Contacts of an EVD Case(LEVELS OF EXPOSURE)High risk exposures Percutaneous, e.g. the needle stick, or mucousmembrane exposure to body fluids of EVD patient. Direct care or exposure to body fluids of an EVDpatient without appropriate personal protectiveequipment (PPE) Laboratory worker processing body fluids ofconfirmed EVD patients without standard biosafetyprecautions. 36. Low risk exposures Household member or other casual contactwith anEVD patient Providing patient care or casual contact without high-riskexposure with EVD patients in health carefacilities in EVD outbreak affected countriesNo known exposurePersons with no known exposure in an EVD outbreakaffected country in the past 21 days with no low risk orhigh risk exposures. 37. DIFFERENTIAL DIAGNOSIS Malaria Dengue Typhoid fever Shigellosis Cholera Leptospirosis Rickettsiosis Relapsing fever Other viral haemorrhagic fevers. 38. DIAGNOSIS Ebola virus infections can be diagnosed in alaboratory through several types of tests: Antibody-capture enzyme-linked immunosorbentassay (ELISA) -NP is one of the major viral structuralcomponents Antigen detection tests Serum neutralization test Reverse transcriptase polymerase chain reaction (RT-PCR)assay Electron microscopy Virus isolation by cell culture. 39. Samples from patients are an extreme biohazard risk;testing should be conducted under maximumbiological containment conditions. 40. CDC- DiagnosisTimeline of Infection Diagnostic tests availableWithin a few days after symptoms beginAntigen-capture enzyme-linkedimmunosorbent assay (ELISA) testingIgM ELISAPolymerase chain reaction (PCR)Virus isolationLater in disease course or after recovery IgM and IgG antibodiesRetrospectively in deceased patientsImmunohistochemistry testingPCRVirus isolation 41. When Specimens Should BeCollected for Ebola Testing Ebola virus is detected in blood only after onset ofsymptoms, most notably fever. It may take up to 3 days post-onset of symptoms forthe virus to reach detectable levels. Virus is generally detectable by real-time RT-PCRfrom 3-10 days post-onset of symptoms, but has beendetected for several months in certain secretions. 42. Specimens ideally should be taken when asymptomatic patient reports to a healthcare facilityand is suspected of having an EVD exposure However, if the onset of symptoms is