Ebola Virus Disease: Epidemiology and Impact

This assignment requires students to analyze a dataset of historical Ebola virus disease outbreaks. The data includes details such as the year, country, species of Ebola virus involved, morbidity (number of reported cases), and mortality (number of deaths) for various outbreaks. Students are expected to examine this data to identify trends in outbreaks over time, geographical patterns, and potential relationships between different variables. The analysis should provide insights into the epidemiology and impact of Ebola virus disease.

Running head: AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
An overview: global travel with respect to Ebola
Name of the Student
Name of the University
Author Note

1AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
Background- An increase in the international journeys exposes the travellers to high
risks of many infectious heath disorders. It is important to provide preventive measures by
circulating information about the mode of transmission and promote well-being to those who
travels frequently to countries with high risk (Merrill 2015). World Health Organisation
(WHO) have implemented the primary strategies through vaccination, but with 900 million
hike in international travellers occurring every year, it is essential to address other preventive
measures to reduce the risk factors both in national and international wise (World Health
Organization 2013) . The following essay discusses the safety measures while travelling in
context to Ebola virus and for this a detailed understanding of this virus with respect to
precautions and preventions are required.
History- Ebola is a severe viral disease often observed fatal in humans. The largest
outbreak of Ebola till date was recorded from West Africa, particularly from Guinea, Sierra,
Liberia and Leone (Fisman Khoo and Tuite 2014). 7178 cases of Ebola Virus Disease (EVD)
with 3338 deaths were reported on October 1, 2014 (Fasina et al. 2014). Apart from this
incident, 20 cases of EVD were reported from Nigeria, but after this no such severe cases of
EVD were observed since September 2014 (Weyer Grobbelaar and Blumberg 2015). The 20
cases that were reported resulted due to a particular importation through a traveller who was
returning on July 2014 from Liberia (Shuaib et al. 2014). Ebola virus (Zaire ebolavirus) is
responsible for hemorrhagic fever with increased rate of fatality. Till date five viruses of
genus Ebola belonging to the family of Filoviridae are identified in which four viruses
causes human EVD and the fifth species has been found in primates of nonhuman in nature
(NHPS) (Rewar and Mirdha 2014). The species are Bundibugyo ebolavirus (BDBV), Zaire
ebolavirus (EBOV), Sudan ebolavirus (SUDV), Reston ebolavirus (RESTV) and Côte
d’Ivoire ebolavirus (TAFV) respectively. The transmission of this virus occurs by direct

2AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
contamination of blood, fluids of the body or derma of patients with EVD or through dead
bodies due to this disease (Gebretadik et al. 2015). The pathogenic nature of these viruses
varies, with EBOV being lethal to a great extent in humans.
Pathophysiology- Zaire (EBOV) replications produce large quantity of virus found
in monocytes, dendritic cells and macrophage cells. The chemical signals of high
inflammation are released due to triggered monocytes (Falasca et al. 2015). Endothelial cells,
liver cells, macrophages and monocytes are prone to this infection. This virus first infects the
macrophages leading to cellular death and infection in endothelial cells occurs after 3 days of
exposure. The vascular injury caused by breakdown of endothelial cells attributes to
glycoproteins (GP) of EBOV. The affected people with haemorrhage undergo edema with
hypovolemic shock. A small soluble glycoprotein (SGP) is secreted just after the infection.
This glycoprotein attaches the virus to endothelial cells by forming one trimetric complex.
The (SGP) interferes with neutrophils signalling by forming a dimer protein evades the virus
to immune system by inhibiting the action of neutrophil. These infected white blood cells
pass the virus throughout the entire body into the organs such as liver, lungs, lymph nodes
and spleen (Paessler and Walker 2013). The presence of virus within the cells causes’ cell
damage and releases the chemical signals such as IL-6, IL-8 and TNF-Ω causing fever and
inflammatory symptoms. The blood vessels integrity is reduced by the infection in
endothelial cells which increases (GP) synthesis which in turn decreases the specific
integrins. Lack of these integrins causes liver damage resulting in improper clotting. The
proteins of EBOV blunt the immune system of humans by interfering the cell’s production
ability with consequent response towards interferon proteins such as interferon alpha, beta
and gamma (Meyer and Ly 2016).
Mode of transmission- Identification of natural host reservoir of Ebola virus and how
the virus appears in human at beginning of the outbreak are yet to be known. According to

3AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
some scientists, the first person got infected through a direct contact with an animal such as
primates or fruit bat infected by this virus. This condition is termed as spillover event
(Chowell and Nishiura 2014). This then goes on transmitting other person affecting a large
count of individuals. It is believed that the primates in past got affected by Ebola and people
got infected too when they came in contact or consumed the infected primates. The mode of
transmission of this virus occurs through various ways. The Ebola spreads through skin that
is broken or via mucous membrane present in eyes, mouth and nose (Judson Prescott and
Munster 2015). The virus spreads through blood or body fluids such as saliva, sweat, urine,
semen, vomit and breast milk of an Ebola affected person. Other mode of transmission is
through virus contaminated needles and injections. Transmission through fruit bat or apes
and monkeys infected by this virus is also noted (Weingartl et al. 2012). Ebola is not an air
borne disease neither it spreads through water or food. Transmission through mosquitoes or
any other insects are not observed. This infection has been reported to confined species of
mammals such as humans, apes and bats and hence plays active role in spreading the virus.
The risk of transmission increases significantly when directly coming to the patient contact at
the acute phase of the disease (Shears and O'Dempsey 2015).
Incidence and prevalence of Ebola cases- The incidence of EVD and its current
prevalence with respect to last few years is being tabulated in the Appendix comprising the
morbidity and mortality numbers.
Incubation period of Ebola- Ebola virus can thrive in liquid medium or the materials
that are dry in nature. The gamma irradiation inactivates the virus along with 60 minutes
heating at a temperature of 60°C or 5 minutes of boiling. Bleaching with sodium hypochlorite
and similar disinfectants can reduce their sensitivity. On the other hand, freezing them does
not exert any affect on their sensitivity (Passi et al. 2015). The incubation duration that is the
time period between the appearance of the first symptom and the infection varies between 4-

4AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
10 days, sometimes the incubation starts from early 2 days extending to 21 days. The case
fatality rates (CFRS) of the ZEBOV infections vary from 44% to 90% (Nanclares et al. 2016).
The series of symptoms varies from individual to individual and manifestations include
severe pain, feeling nausea and ill followed by bleeding. The fever in the second week either
decreases or causes failure of multiple organs in the patient. The range of the mortality rates
are species dependent and depends on the virus strains of the species. Early symptoms are
common to bacterial infections that are less severe such as malarial fever, influenza fever or
typhoid fever. Initially, the fever is 101.8° Fahrenheit followed by pain, headache, throat
sore, bleeding, nausea, dizziness with fatigue feeling. With the progression of the disease, the
patient develop more critical issues such as faeces characterised by bloody and dark
appearances, vomiting with blood, diarrhoea and eyes showing red appearances resulting in
sclerotic arterioles haemorrhage. Other signs of secondary infection show tachycardia,
decrease in blood pressure and hypovolemiatic shock (Beeching Fenech and Houlihan 2014).
In certain cases the infected person starts bleeding from injures that is partially healed or site
of injection in skin epidermis. It occurs when the virus affects blood platelets which in turn
develop sutures into the capillary walls. Ebola alters the levels of white blood corpuscles and
platelets, making the blood clot more difficult with consequent haemorrhage over 50%
patients (Goeijenbier et al. 2012).
Diagnosis with possible treatment- The process of diagnosis is difficult in person with
Ebola as the initial symptoms are nonspecific such as fever and often found in patients having
malarial fever and typhoid fever. If any symptoms corresponding to Ebola are noticed, the
person should be kept in isolation with prior notification to health professionals. Samples
should be collected to confirm the infection. Detection of Ebola virus in the blood starts only
after the symptoms onset through fever. It takes minimum 3 days to reach the detection stage.
No such FDA-treatment such as treating by antiviral drugs is available for Ebola (Chmielecki

5AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
2015). But by following certain basic interventions in early stage can improve survival
chances significantly. The strategic interventions are provided by intravenous fluids and by
balancing the electrolytes of the body salts. Maintaining the oxygen rate with balanced blood
pressure and taking proper care to treat other infections if any, reduces the risk factors.
Experimental treatments surrounding Ebola are under process but yet to be tested for
effective safety implications. A good caring support can recover the incidence of Ebola by
improving the immunity power of the patient. The antibodies developed by the recovered
patients last for more than 10 years. It is still unknown that the people who recover are life
immune or is there any possibility of getting infected by other species of Ebola. The
recovered people have showed complications in joint and visualising (Blaser 2014).
Vaccination- Treatment through vaccination in an experiment showed increased
protection against the fatal virus that was trailed in Guinea (Kaushik et al. 2016). The vaccine
that was used named rVSV-ZEBOV was experimented on 11841 people in 2015. No such
cases of Ebola was recorded after 10 days of vaccination among 5837 people whereas 23
cases were there 10 days post vaccination among them who did not take the vaccination.
WHO along with Ministry of Heath of Guinea collaborated with international partners in a
protocol of ring vaccination. In this trail, some rings were vaccinated immediately after a
detection of a case whereas the other rings were vaccinated after 3 weeks (Shu-Acquaye
2017).
Prevention- Controlling the outbreak of this disease needs interventional package for
managing the case, survey study with contact tracing, well equipped laboratory services,
mobilising socially and controlled burials. The outbreaks can be successfully controlled by
community engagement through increasing awareness about the risk factors for this infection
and providing protective measurements such as through vaccination can thereby minimise
human transmission. The messages of risk reduction are based on factors such as by reducing

6AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
the transmission risk from wild animals to humans by avoiding contact with infected primates
or fruit bats and avoiding their raw meat consumption. The handling of these animals should
be done with gloves and protective clothing. The second factor is reducing the transmission
risk between the same species such as human from coming in direct contact with Ebola
detected patients specially body fluids of them. Patients should be handled by wearing gloves
and protective clothing with regular hand sanitising. The third factor is by reducing the risk
caused by sexual transmission (Regmi Gilbert and Thunhurst 2015).
Developing control measures by heath workers- The health workers should follow
standard precautions during the care of patients’ diagnosed by this viral symptom. They
should control the transmission by maintaining hand and respiration hygiene along with
protective equipment to avoid contact with materials infected and safe disposal of injections.
The health workers allocated to the suspected patients should take extra control measures in
order to avoid direct contact with blood and fluids of the patient’s body. Workers in close
proximity of 1 metre of the patients should use mask, gloves, goggles with protective gown.
Apart from the heath workers, the workers in the laboratory are also prone to infection.
Proper handling of the infected sample should be carefully handled by staffs well trained and
the sample should be processed in well equipped laboratories (West and von Saint André-von
Arnim 2014).
Roles of WHO in preventing the Ebola outbreaks- Ebola outbreaks are controlled by
the WHO (World Health Organisation), an international Committee on Scientific and
Technical Coordination. This committee implements measures to control the daily life
activities conducted by certain working subgroups. The management team for patient isolates
the clinical cases into quarantine ward and trains to equip proper preventive measures such as
use of gloves, mask and protective clothes and also provides medical care corresponding to
symptomatic theory in order to maintain the vital functioning of the body. The committee

7AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
based on coordination controls all the epidemic activities by conducting meetings and writing
reports for public related health authorities. The surveillance team on epidemiology finds the
cases by verifying the case related rumours. The team for hygiene and sanitising disinfects
and buries all the Ebola related dead bodies safely. The laboratory team collects, stores and
ships the samples to confirm the diagnosis (Gostin and Friedman 2015).
Remarks- It can be concluded from the above discussion that the travellers returning
from the affected regions should apply necessary measures to prevent the infection if any
disease related symptoms starts developing within 21 days of return. The travellers specially
the health workers suspecting Ebola symptoms should seek medical attention. They should
report the travel history to the physician in order to under the root cause of the symptoms and
hence proceed for prevention strategies.

8AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
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9AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA
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Appendix:
Year Country Species of
Ebola virus
Morbidity Mortality
2017 Demographic
Republic of
Congo
Zaire sp. 8 4
2015 Italy Zaire sp. 1 0
2014 Spain Zaire sp. 1 0
2014 Demographic
Republic of
Congo
Zaire sp. 66 49
2014 United
Kingdom
Zaire sp. 1 0
2014 USA Zaire sp. 4 1
2014 Mali Zaire sp. 8 6
2014 Senegal Zaire sp. 1 0
2014 Nigeria Zaire sp. 20 8
2014 to 2016 Liberia Zaire sp. 10675* 4809*
2014 to 2016 Sierra Leone Zaire sp. 14124* 3956*
2014 to 2016 Guinea Zaire sp. 3811 2543
2012 Demographic
Republic of
Congo
Bundibugyo sp. 57 29
2012 Uganda Sudan sp. 7 4
2012 Uganda Sudan sp. 24 17

12AN OVERVIEW: GLOBAL TRAVEL WITH RESPECT TO EBOLA