Ebola virus November 2014- A final update?

November 2014
11/02/14 Dr. Vaibhav V. Rajhans 1

 This is a group of viral diseases, apparently
zoonotic in nature, with typical hemorrhagic
features caused by viruses belonging to two
families- Arenavirus and Filovirus
 Hemorrhagic manifestations can be seen in
other viral diseases also.
 Arenavirus and Filovirus have localised
distribution in South America and Africa

 Lymphocytic Choriomeningitis [LCM] virus
 Junin virus
 Machupo virus
 Lassa fever virus

 Filum- thread
 Size- 80 to 800-1000 nm
 Two important viruses- Marburg and Ebola
 These virus are among the most virulent
pathogens known to infect humans,
categorized under Bio safety level- 4
 Both these virus are included in Class A of
Bioterrorism, along with Small pox, Plague etc
and other virus causing hemorrhagic fever

 The research on these viruses is still in
primitive condition, mostly due to-
 Difficulty in field studies in remote areas
 Sudden and unexpected occurrence of cases
 Very brief duration of outbreaks
 Requirement of High level containment- BSL 4

 First observed in 1967 In Marburg, Frankfurt
{Germany} and Belgrade {Yugoslavia} in
Laboratory workers.
 Source- African green monkeys from Uganda
 Person to person transmission
 Fatality rate in primary cases was 30%,
secondary cases were non-fatal

 Virus was then grown in tissue culture and
guinea pigs from blood and tissues of patients
 Virus appeared to persist in the body and
isolated even after 80 days of onset of illness
from semen and anterior chamber of eye
 A case of sexual transmission has also been
recorded

 This virus is transmitted by direct contact
- with the blood, body fluids and tissues of
infected persons
 Transmission of the Marburg virus also occurs
by handling ill or dead infected wild animals
(monkeys, fruit bats)

 In Africa, the Old World fruit bats of the
family Pteropodidae, particularly species
belonging to the genus Rousettus aegyptiacus are
considered natural hosts for Marburg virus.
 There is no apparent disease in the fruit bats

 (formerly known as Marburg haemorrhagic
fever)
 A severe and highly fatal disease
 Rare, but have a capacity to cause dramatic
outbreaks with high fatality.

 Illness begins abruptly, with severe headache
and severe malaise
 Many patients develop severe haemorrhagic
manifestations between days 5 and 7
 fatal cases usually have some form of bleeding,
often from multiple sites

 After the first appearance, Marburg virus again
appeared in 1975 in South africa [3 cases]
 And In 1980 in Kenya [2 cases]
 And then in the Democratic Republic of Congo
from 1998-2000 and the outbreak in Angola in
2005, both having 80% fatality

Marburg virus infections can be diagnosed
definitively only in laboratories, by
•enzyme-linked immunosorbent assay (ELISA);
•antigen detection tests;
•serum neutralization test;
•reverse-transcriptase polymerase chain reaction
(RT-PCR) assay
•virus isolation by cell culture.

 No specific antiviral treatment or vaccine is
available.
 The predominant treatment is general
supportive therapy

 Avoid pigs becoming infected through contact
with fruit bats
 Reducing the risk of bat-to-human
transmission by wearing gloves and other
appropriate protective clothing
 avoid any exposure to blood and body fluids
and to direct unprotected contact with possibly
contaminated environment

 Samples taken from suspected human and
animal Marburg cases for diagnosis should be
handled by trained staff and processed in
suitably equipped laboratories
 People who have died from Marburg should be
promptly and safely buried.

 Morphologically similar to Marburg virus but
antigenically different
 First cases noticed in 1976, in Sudan and Zaire
[Democratic Republic Of Congo] beside Ebola
river
 Reservoir of virus or natural course of this
virus are still unclear but Fruit bats of the
Pteropodidae family are considered to be the
natural host of the Ebola virus

Species name Virus name (Abbreviation)
Bundibugyo ebolavirus Bundibugyo virus (BDBV;
previously BEBOV)
Reston ebolavirus Reston virus (RESTV;
previously REBOV)
Sudan ebolavirus Sudan virus (SUDV;
previously SEBOV)
Taï Forest ebolavirus Taï Forest virus (TAFV;
previously CIEBOV)
Zaire ebolavirus Ebola virus (EBOV;
previously ZEBOV)

 Ebola virus disease (formerly known as Ebola
haemorrhagic fever) is a severe, often fatal
illness, with a case fatality rate of up to 90%
 one of the world’s most virulent diseases
 Mode of transmission- by direct contact with
the blood, body fluids and tissues of infected
animals or people
 Severely ill patients require intensive
supportive care

 High risk group- health workers, family
members and others in close contact with sick
people and deceased patients.
 Ebola virus disease outbreaks can devastate
families and communities, but the infection can
be controlled through appropriate protective
measures

 Fever (greater than 38.6°C or 101.5°F)
 Severe headache
 Muscle pain
 Weakness
 Diarrhea
 Vomiting
 Abdominal (stomach) pain
 Lack of appetite

 Symptoms may appear anywhere from 2 to 21
days after exposure to ebolavirus, although 8-
10 days is most common.
 Some who become sick with Ebola are able to
recover. However, patients who die usually
have not developed a significant immune
response to the virus at the time of death.

 Endothelial cells, mononuclear phagocytes and
hepatocytes are the main targets of infection
 After infection, a secreted glycoprotein (sGP)
known as the Ebola virus glycoprotein (GP) is
synthesized
 Ebola replication overwhelms protein synthesis
of infected cells and host immune defenses.

 The virus then binds to the endothelial cells
lining the interior surface of blood vessels
 These white blood cells also serve as carriers to
transport the virus throughout the entire body
to places such as the lymph nodes, liver, lungs,
and spleen.
 Fever and inflammation ensues

 The cytopathic effect,
from infection in the
endothelial cells,
results in a loss of
vascular integrity
 And damage to the
liver leads to
coagulopathy

 1976- Zaire/ DROC- 318- 88%
 1979- Sudan- 34- 65%
 1994- Gabon- 49- 59%
 1995- Zaire/ DROC- 315- 81%
 1996- Gabon- 91- 72%
 2002- Gabon and Zaire/ DROC- 122- 79%
 2005- Cuvett Quest Region- 12- 75%

 The 2014 Ebola outbreak is one of the largest
Ebola outbreaks in history and the first in West
Africa. It has principally affected four countries
in West Africa:
 Guinea, Liberia, Sierra Leone and Nigeria

 The World Health Organization, in partnership
with the Ministries of Health in Guinea, Sierra
Leone, Liberia, and Nigeria reported 13567
suspect cases of EVD, including 7728
laboratory-confirmed cases, and 4960 deaths.
 CFR- 64.18 %
Ref: http://www.cdc.gov
updated on 31.10.2014

 WHO declared the outbreak an international
public health emergency on 8 August 2014
 Ram Manohar Lohia Hospital in New Delhi
has been designated as a treatment centre for
Ebola Virus Disease (EVD) cases in India

 Researchers believe that the first human case of
the Ebola virus disease leading to the 2014
outbreak was a 2-year-old boy who died 6
December 2013 in the village of Meliandou,
Guéckédou Prefecture, Guinea. His mother, 3-
year-old sister and grandmother then became
ill with symptoms consistent with Ebola
infection and died. People infected by those
victims spread the disease to other villages.

 In Guinea-
 total 1667 cases
 1409 cases- laboratory confirmed
 1018 deaths
 In Liberia-
 Total 6535 clinical cases
 2515 cases laboratory confirmed cases
 2413 deaths

 In Sierra Leone
 Total 5338 cases
 3778 laboratory-confirmed cases
 1510 deaths
 In Nigeria-
 Total 20 cases
 19 laboratory confirmed cases
 8 deaths.

 http://www.who.int/csr/disease/ebola/map
s/en/
http://www.who.int/cs
r/disease/ebola/maps/
en/

Country Total Cases
Laboratory
-
Confirmed
Cases
Total
Deaths
Mali 1 1 1
Senegal 1 1 0
Total 2 2 1

Country Total Cases
Laboratory
confirmed
Cases
Total
Deaths
Nigeria 20 19 8
Spain 1 1 0
United
States 4 4 1
Total 25 24 9

 The outbreaks of Ebola Virus Disease (EVD) in
Senegal and Nigeria were declared over on 17
October and 19 October 2014, respectively. A
national EVD outbreak is considered to be over
when 42 days (double the 21-day incubation
period of the Ebola virus) has elapsed since
the last patient in isolation became laboratory
negative for EVD.

 The Guinean Ministry of Health, the Ministry
of Health and Sanitation of Sierra Leone, the
Ministry of Health and Social Welfare of
Liberia, and the Nigerian Ministry of Health
worked with national and international
partners to investigate and respond to the
outbreak.

Ebola virus infections can be diagnosed
definitively in a laboratory by
•Antibody-capture enzyme-linked immunosorbent
assay (ELISA)
•Antigen detection tests
•Serum neutralization test
•Reverse transcriptase polymerase chain reaction
(RT-PCR) assay
•Electron microscopy
•Virus isolation by cell culture.

 No licensed vaccine for EVD is available.
Several vaccines are being tested, but none are
available for clinical use.
 Severely ill patients require intensive
supportive care. Patients are frequently
dehydrated and require oral rehydration with
solutions containing electrolytes or intravenous
fluids.
 No specific treatment is available. New drug
therapies are being evaluated.

 An experimental treatment is a combination or
cocktail of three monoclonal antibodies that is
designed to bind to the protein of the Ebola
virus, neutralizing the virus so it can’t do any
further damage.

 Reducing the risk of wildlife-to-human
transmission from contact with infected fruit
bats or monkeys/apes and the consumption of
their raw meat
 Animals should be handled with gloves and
other appropriate protective clothing
 Animal products (blood and meat) should be
thoroughly cooked before consumption.

 Close physical contact with Ebola patients
should be avoided, particularly with their
bodily fluids
 Gloves and appropriate personal protective
equipment should be worn when taking care of
ill patients at home
 Regular hand washing is required after visiting
patients in hospital, as well as after taking care
of patients at home.

 Communities affected by Ebola should inform
the population about the nature of the disease
and about outbreak containment measures,
including burial of the dead
 People who have died from Ebola should be
promptly and safely buried

 On 21 July, three Dwarka, Delhi residents were
placed under surveillance after WHO
confirmation that one of the passengers on the
flight had tested positive for Ebola; however,
none of the three had shown any symptoms of
the disease
 On 8 August, India placed all of its airports on
high alert and stepped up surveillance of all
travellers entering the country from Ebola-affected
regions

 From 9 August, passengers coming from Ebola-affected
countries were made to complete a
form before landing; the form had a checklist
for symptoms and asked travelers from West
Africa for information about places visited,
length of stay and other important information.
 A 24-hour emergency phone helpline is
functional. Its numbers are (011)-23061469, 3205 and 1302.

 The estimated 47,000 Indians in the affected
countries were contacted by area diplomatic
missions and supplied with educational
material about the disease.
 No confirmed case of EVD has been reported
from India until now.

 This deadly outbreak stirred the whole world
with the grave consequences of so many
deaths.
 All we can do is that take all the possible
rational effective measures to contain this
virulent pathogen and treat those who
acquired it, with great care.
 Lets hope that this outbreak will end soon as it
did in Senegal and Nigeria.
 Wish the best to us all.

 http://www.cdc.gov/vhf/ebola/outbreaks/g
uinea/
 http://www.cdc.gov/vhf/ebola/outbreaks/2
014-west-africa/case-counts.html
 http://www.who.int/csr/don/archive/diseas
e/ebola/en/
 http://www.who.int/csr/disease/ebola/en/
 http://en.wikipedia.org/wiki/2014_West_Afri
ca_Ebola_virus_outbreak#India
 Ananthanarayan and Paniker’s Textbook of
Microbiology, University p 11/02/14 Dr. Vaibhav V. Rajhans ress, 9th ed. 58

Ebola virus November 2014- A final update?

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to Ebola virus November 2014- A final update?

Similar to Ebola virus November 2014- A final update? (20)

Recently uploaded

Recently uploaded (20)

Ebola virus November 2014- A final update?