Vnu – hanoi university of sciences

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VNU – Hanoi University of sciences Faculty: Environmental science Subject: Biology L111. evolution and diversity Teacher: Asso. Prof. Thuy Tran Van Class: K57TTKHMT

Transcript of Vnu – hanoi university of sciences

VNU – Hanoi University of sciences

Faculty: Environmental scienceSubject: Biology L111. evolution and diversityTeacher: Asso. Prof. Thuy Tran VanClass: K57TTKHMT

Le Thi Van Anh

Pham Thi Minh Huyen

Ho Nguyen Hoang

Duong Nhat Khanh

Ebola virus

Content

- General information- What is Ebola virus?- How does Ebola virus spread?- How do we adapt with Ebola virus?

-Pham Thi Minh Huyen- Le Thi Van Anh- Ho Nguyen Hoang- Duong Nhat Khanh

Nearly 40 years ago, a young Belgian scientist travelled to a remote part of the Congolese rainforest - his task was to help find out why so many people were dying from an unknown and terrifying disease. In September 1976, a package containing a shiny, blue thermos flask arrived at the Institute of Tropical Medicine in Antwerp, Belgium. Working in the lab that day was Peter Piot, a 27-year-old scientist and medical school graduate training as a clinical microbiologist. "It was just a normal flask like any other you would use to keep coffee warm, " recalls Piot, now Director of the London School of Hygiene and Tropical Medicine. But this thermos wasn't carrying coffee - inside was an altogether different cargo. Nestled amongst a few melting ice cubes were vials of blood along with a note. It was from a Belgian doctor based in what was then Zaire, now the Democratic Republic of Congo - his handwritten message explained that the blood was that of a nun, also from Belgium, who had fallen ill with a mysterious illness which he couldn't identify.

It is the river where hide the secret about one danger epidemic

An old story

Yambuku Where the Ebola infections were first identified in the day 26/08/1976.

In this first Ebola epidemics, 318 people were infected, of which 280 people died in Congo and 284 cases, 151 deaths in a region of Sudan. It means that the mortality rate of the disease up to 90 percent (10 were infected => 9 were death).

These were the three questions Piot and his colleagues asked:

1. How did the epidemic evolve? Knowing when each personcaught the virus gave clues to what kind of infection this was - from here the story of the virus began to emerge.

2. Where did the infected people come from? The team visited all the surrounding villages and mapped out the number of infections - it was clear that the outbreak was closely related to areas served by the local hospital.

3. Who gets infected? The team found that more women than men caught the disease and particularly women between 18 and 30 years old - it turned out that many of the women in this age group were pregnant and many had attended an antenatal clinic at the hospital.

The mystery of the virus was beginning to unravel. The team then discovered thatthe women who attended the antenatal clinic all received a routine injection. Each morning, just five syringes would be distributed, the needles would be

reused and so the virus was spread between the patients.

And the virus can be transmitted by skin because protective gears are incomplete,...

The recent Ebola outbreak that started in March 2014, however, has reached epidemic proportions and has killed more than 6000 persons as of December 2014.

This outbreak has been centered in West Africa, an area that had not previously been affected by the disease. The toll has been particularly grave in three countries:

Guinea, Liberia, and Sierra Leone.

Ebola deaths since 1976

Figures accurate from 4-6 October, depending on country. Death toll in Liberia includes probable, suspect and confirmed cases, while in Sierra Leone and Guinea only confirmed cases are shown

In the absence of any vaccine or cure, the advice for this outbreak is much the same as it was in the 1970s. "Soap, gloves, isolating patients, not reusing needles and quarantining the contacts of those who are ill - in theory it should be very easy to contain Ebola," says Piot.

What is symptoms of Ebola disease? 

• According to WHO, sudden fever, stress, muscle pain, headache and sore throat are typical symptoms of Ebola virus disease known.

• This was followed by vomiting, diarrhea, rash, renal dysfunction and liver, and in some cases bleeding both inside and outside (Ebola can cause bleeding from the eyes,

ears, nose , mouth and rectum).• The incubation period of the disease Ebola virus ranges from 2 to 21 days after

exposure to the pathogen until the first symptoms. • Results of laboratory studies showed that blood cell and platelet counts are low Ebola

virus infections while higher than normal liver enzymes. • According to WHO, the patient will be contagious to other

people when they start having symptoms. During the incubation period, they are not likely to spread.

EBOLA1. Definition and structure

Definition - Ebola is a viral illness of which the initial

symptoms can include a sudden fever, intense weakness, muscle pain and a sore throat, And that is just the beginning: subsequent stages are vomiting, diarrhoea and - in some cases - both internal and external bleeding. (according to the World Health Organization (WHO).

- Subtype: Zaire, Sudan, Reston, and Côte d'Ivoire (Ivory Coast)

Structure Rod-shape or 6-shape Virion: filamentous, 970 nm long, 80 nm in

diameter, enveloped Genome: approximately 19 kilobase

negative-sense, single-stranded RNA Proteome: 7 sequentially arranged

proteins Infection: initiates by the attachment of GP

glycoprotein to host receptors RNA Transcript: 5' methyl cap, 3' poly-A

tail

Structure

Structure Glycoprotein is a

transmembrane fusion protein.

Structure The viral

membrane (viral envelope) may contain human proteins

Structure VP40 and VP24 are

Ebola major and minor matrix proteins.

Structure Ebola RNA is

packed with the NP protein.

Structure L stand for the

large Ebola protein – the polymerase .

Structure V35 and V30 are

the minor Ebola protein.

Structure The budding viral

particle is wrapped in the lipid membrane taken from the human cell.

Genome of Ebola virus RNA Transcript: 5' methyl cap, 3'

poly-A tail3-leader-NP-VP35-VP40-GP/

sGP-VP30-VP24-L-- trailer-5'

How does Ebola virus spread?

- Transmission from wild animals.

- Human-to-human transmission.

Natural Ebola virus hosts: fruit bats of the Pteropodidae family

Ebola is introduced into the human population: through close contact with the blood, secretions, organs or other bodily fluids of infected animals (chimpanzees, gorillas, fruit bats, monkeys, forest antelope and porcupines found ill or dead or in the rainforest)

Transmission from wild animals

Direct contact : through broken skin or mucous membranes, with the blood, secretions, organs or other bodily fluids of infected people.

Indirect contact: with surfaces and materials (e.g. bedding, clothing) contaminated with these fluids.

Human-to-human transmission

The maximum incubation period for Ebola :21 days

Genome: approximately 19 kilobase negative-sense, single-stranded RNA

Binding and entry of an infecting virion virus protein expression + RNA replication assembly and release new virion

The viral life cycle

The viral life cycle

As viruses replicate, their genome changes. EPA/Ahmed Jallanzo

The Broad Institute/Harvard University study

In order to better understand the origin and transmission of the current outbreak in West Africa

in collaboration with the Sierra Leone Ministry of Health, sequenced 99 virus genomes from 78 patients.

How does Ebola evolve?

Researching about early and late in the outbreak how genetic changes ( which make virus easier to spread) manage future outbreaks

How does Ebola evolve?

4. How to prevent Ebola

IN DAILY LIFE

Wash your hands

Avoid contact with anyone you believe is infected

Disinfect any potentially infected areas

Know the warning signs

Know what to do

Do not touch bats, chimpanzees, gorillas or monkeys

Avoid dead bodies

Avoid travelling to affected countries

Use condoms

4. How to prevent Ebola

INTERACTIVE WITH INFECTED PEOPLE

Suit Up

Ebola fears prevent the world from developing

So far, no vaccine or cure is available. Due to the current problems, finding the

ways out is very important. For everyone, just protect yourself by doing

the rules above.

Conclusion:

BBC NEWS Wiki.org The conversation - http://theconversation.com/genetic-

evolution-how-the-ebola-virus-changes-and-adapts-31525 Els Article - http://www.els.net/WileyCDA/ElsArticle/refId-

a0001022.html BBC World Service Sciencemag - http://www.sciencemag.org/site/extra/ebola/ https://flipboard.com/section/plos-ebola-collection-bRVgYj http://www.ncbi.nlm.nih.gov/genome/viruses/variation/ebol

a/ http://www.viprbrc.org/brc/home.spg?decorator=filo_ebola David M. Knipe, Peter M. Howley, et al.. Fields’ Virology. 5th

edition. 2007 Lippincott Williams & Wilkins. USA, http://www.cdc.gov/vhf/ebola/

References