Ebola Virus By: Giselle and Matt

Family of Ebola Virus Filoviridae Comes from the Latin filo meaning “threadlike” Two members 1.Marburg 2.Ebola Virus  Five Species 1.Zaire 2.Sudan 3.Reston 4.Ivory Coast 5.Bundibugyo

Filovirus Very in shape long sometimes branched filaments Shorter filaments shaped like a “6” or “U” sometimes a circle. Filaments measure from 80nm (Average) to 14,000nm. Enveloped virion Single-strand negative sense RNA Proteins Five proteins in filoviruses Glycoprotein Nucleocapsid Transcriptase-polymerase RNA dependent RNA transcriptase polymerase matrix

History Discovered in Received it named from the first victims found from the Ebola River Valley in the Democratic Republic of the Congo.

Strains Zaire 90% mortality rate. 276 out of 300 died. Sudan 50% morality rate. 150 out of 285 died. Reston Found 1989 infected monkeys in the Philippines The only airborne strain of Ebola virus. Later found that this strain is not harmful to humans but very devastating to monkeys. However four people known to have developed antibodies to this strain. Ivory Coast Found in monkey being autopsied by a scientist in Scientist became ill from the virus but survived. Bundibugyo Most recently discovered strain of Ebola virus. Has less power to kill when compared to other strains. 25%morality rate. 37 out of 150 died. cdn.creamermedia.co.za/assets/articles/images/ resized/38935_resized_newebolastrain.jpg

Symptoms High fever Muscle aches Sore throat Fatigue Followed by: Stomach pain Diarrhea Rash Vomiting Some may experience: Internal and external bleeding SZJ1Vr5vM:

Virion Replication Enveloped viron – membrane surrounding the virus. Phospholipids bilayer – With embedded proteins (spikes) Facilitate penetration of the virus into the host’s cell’s cytoplasm. Adsorption – Spike shape complements a host’s cell protein. – Ebola attaches and is endocytosed into the cell. Penetration 1.The virus membrane fuses to the hosts membrane. 2.Nucleocapsid is released into the cytoplasm. Synthesis – Occurs in the cytoplasm – Make more 1.Capsid proteins 2.Genome – Host uses host mechanisms Transcription- used to synthesize (-) sense RNA for encapsulation Translation- make more viral proteins.

Maturation – Assembly of new virions made inside the cytoplasm. Release – The Ebola virus uses the TSG101 pathway. This is the same pathway as HIV. – Exocytosis Newly formed Ebola Virus bud from cell membrane and released. Infected host cell remains alive to continue viral replication. Virion Replication Continued..

Cell Ebola targets The main cells it will attack are fibroblastic reticular cells which form much of the connective tissue. These cells are under the skin and close by to blood and lymph vessels. This allows the virus to spread easily in the body. Ebola will then go on and attack any other connective tissue and epithelial tissue. This is what causes the hemorrhaging portion of the symptoms. The virus then moves on to liver and kidney cells.

Evading the Immune System Ebola once again works similar to HIV in how it evades the immune system. There is a cellular protein called tetherin This protein does not save the infected cell. It prevents the virions from budding off into endosome and escaping. Ebola disables tetherin like HIV does. This allows the virus to bud out of the cell.

Transmission from host to host The virus spreads similar to HIV. – It spreads through bloody fluids such a blood, semen, and feces. – The only exception is the Reston Ebola virus shown to be air born lucky for us it only attacks monkeys. The outbreaks usually happen when a human gets the disease from an animal. – This is known as a zoonotic infection (from animal to human). – Then the infected person infects family and friends and hospital staff. This can be contributed to the fact these outbreaks happen some of the poorest nations. – In the nations of Africa there is a severe lack of resources especially in medicine. The nurses have limited or no personal protective equipment. – They also have to reuse syringes that do not get cleaned properly. – This not only spreads Ebola, but it also spreads HIV and other diseases.

Vaccine Experimental vaccine Being evaluated on infected primates. Vaccine has a recombinant inhibitor factor. 33% survival rate Although this experimental vaccine shows promising results there are no anti-viral drugs available for clinical use.

Biohazard The lack of a cure and vaccine makes Ebola a level 4 biohazard. Level 4 biohazards are kept in special labs known as level 4 biosafety labs. 1.The first level is for microbial agents that do not cause harm to humans. 2.The second level is for microbial agents that do cause human disease but transmission is limited. 3.The third level is for microbial agents that cause severe infections and easily transmitted to humans. 4.The fourth level is for microbial agents that have no cure or vaccine. They are also highly contagious and pose a significant health threat.

Treatment Isolation of the virus for 2-22 days. There is no treatment for filoviruses. Treatments of symptoms: Keeping fluid and electrolyte levels balanced. Maintaining blood pressure and oxygen levels. Blood transfusions. Cause of death: Normally Organ shock or failure associated with fluid and blood loss. It is still unknown why some infected recover while others die. But those that die have not had a significant immune response before death ebola-scientist-hmed.300w.jpg

Bioterrorism The possibility of a bioterrorist attack using Ebola is unlikely. The natural reservoir is unknown. The virus is held in highly guarded labs. Ebola would make an effective Weapon because of: the fear it would instill in people. how quickly the virus kills and spreads.