Ebola Virus

Introduction

  • The Ebola virus belongs to Filoviridae family 
  • There are five species 
  • Infection with specific species causes severe disease called Ebola Virus Disease (EVD)
  • The disease progresses to cause internal and external bleeding

CLASSIFICATION 

Text

Structure

Structure

History

  • First appeared in 1976 in Nzara (53% Mortality rate) 
  • Second Ebola virus emerged from Yambuku Zaire (88% Mortality rate)
  • The latter occurred near in a village near Ebola river , from which the virus takes its name 
  • The third strain of Ebola , Ebola Reston (EBOR) , was first identified in 1989 when infected monkeys were imported into Reston , Virginia

outbreaks

outbreaks

Outbreaks

  • The current outbreak in west Africa , (First cases in March 2014) , is the largest and most complex Ebola outbreak since the Ebola was first discovered 

Statistics

Statistics

TRANSMISSION

  • It is thought that fruit bats of the pteropodidae family are natural Ebola virus host
  • Ebola then spreads through human-to-human transmission via direct contact with bodily fluids of infected people and with surfaces and materials contaminated with these fluids  
  • Health care workers have frequently been infected while treating patients with suspected or confirmed EVD
  • Men who have recovered from the disease can still transmit th virus through their semen for up to 7 weeks after recovery

Target cells

  • It attacks dendritic cells which sen signals to activate lymphocyes 

1. Immune system

Target cells

2. Endothelial cells   

  • When Macrophages and monophages is infected they release proteins that trigger coagulation , forming small clots throughout the blood vessels and reducing blood supply to organs  
  • They also produce other inflammatory signalling proteins and nitric oxide , which damage the lining of blood vessels , causing them to leak

Target cells

3. Liver 

  • Ebola wipes out cells required to produce coagulation proteins and other important components of plasma.
  • Damaged cells in the gastrointestinal tract lead to diarrhea that often puts patients at risk of dehydration

Replication

  • It uses a combination of host and viral encoded enzymes along with the host cell structures so that it can replicate and self assemble its components into viral macromolecule inside the host   

Symptoms

vaccines

  • The ambition: to accomplish, within a matter of months, work that normally takes from two to four years, without compromising international standards for safety and efficacy.

  • Two promising candidate vaccines:

 

1. ​cAd3-ZEBOV : 

  • It is derived from a chimpanzee adenovirus
  • genetically engineered to express glycoproteins from the Zaire and Sudan species of Ebola virus
  • Phase 1 commenced in September 2014 , and had been administered to a number of volunteers   

 

2. ​rVSV-ZEBOV : 

  • It uses an attenuated or weakened vesicular stomatitis virus  
  • Genetically engineered by replacing one of stomatitis virus by an Ebola virus gene
  • A single intramuscular injection of the EBOV or MARV vaccine induced completely protective immune responses in non human primates

vaccines

  • A significant number of doses will not be available until late in the first quarter of 2015 under the best conditions

mutations

  • Mutation is a normal process that occurs every generation whenever an organism reproduces
  • Evolution occurs when these mutations are passed down from generation to generation and spread through apopulation , often via natural selection
  • In the case of Ebola, the virus is not mutating "in order to" spread faster and that mutations allowing this occur are not more likely than mutations with any other effect
  • Ebola has high mutation rate , as it is RNA virus and when RNA is copied many more mistakes are made than when DNA is copied
  • Ebola's high mutation rate and rapid rate of replication combine to allow it to evolve quickly    

TREATMENT 

  • The Ebola virus does not have a cure time , Supportive care measures include :

 

  • giving medications to maintain blood pressure

  • managing electrolyte balances

  • providing extra oxygen, if needed

  • providing intravenous fluids to prevent dehydration

  • treating co-existing infections and preventing other infections from occurring

  • Recovery from Ebola depends on good supportive care and the patient’s immune response , People’s immune systems can respond differently to Ebola. While some may recover from the virus without complication , others can have residual effects like joint problems 

TREATMENT 

  • Possible Anti-viral medication :

 

  • Favipiravir
  • BCX4430
  • Brincidofovir
  • JK-05
  • Lamivudine

protection

1-Listen to and follow directives issued by your country’s respective Ministry of Health

2-Understand the nature of the disease, how it is transmitted, and how to prevent it from spreading further

3-If you suspect someone close to you or in your community of having Ebola virus disease, encourage and support them in seeking appropriate medical treatment in a health-care facility .

4- When visiting patients in the hospital or caring for someone at home, hand washing with soap and water is recommended after touching a patient, being in contact with their bodily fluids, or touching his/her surroundings

5-People who have died from Ebola should only be handled using appropriate protective equipment and should be buried immediately by public health professionals who are trained in safe burial procedures

thanks 

 

 

TIME FOR

QUESTIONS

IT'S

Made with Slides.com