1. Background: Morbidity and mortality rates of the
The most widespread
outbreak of Ebola Virus Disease (EVD) since it was first experienced in
1976 was that of the West African epidemic that occurred
from late 2013 through 2016 causing major loss of life and disruption of socioeconomic
activities in the region. The outbreak is uncommon in terms of its duration, number
of cases recorded, fatality and geographical spread. Unlike previous outbreaks,
which lasted for a very short time, the recent case lasted for more than one
year. It occurred mainly in the countries of Guinea, Liberia, and Sierra Leone, the first cases being
recorded in Guinea in December 2013, although EVD was not suspected until much
later in 2013 and not confirmed until March 2014. The disease later spread to
neighboring countries, Senegal and Mali, with minor outbreaks in Nigeria. (WHO
Ebola Response Team, 2014).
Ebola virus, a zoonotic infection-
an infectious disease that is transmissible from animals to humans-, causes a
severe haemorrhagic fever in humans with high case fatality and significant
epidemic potential as shown by the 2014–2016 West African outbreak. It severely
threatened international public health systems in ways they have never been
challenged before. West Africa
experienced the highest epidemic of the virus since the beginning of 2014 infecting
larger number than all other outbreaks combined as reported by WHO, 2016 where
in total: Reported cases =28 646
and Mortality case = 11 323.
This reported cases
indicate the number of people that were confirmed, probable and suspected to be
infected during the study period. However in epidemiology (study of the
distribution and determinants of health conditions), these reported case is
often used more casually to include proportions that are not truly infected. On
the other hand, the mortality case indicates the occurrence of death from the
reported case between 2014-2016. The virus caused significant mortality, with
the case fatality rate i.e the proportion of confirmed Ebola patients who
died from EVD slightly above 70%, while the rate among hospitalized
patients was 57–59%. Although, small outbreaks occurred in Nigeria and Mali, and isolated cases were recorded in Senegal, the United Kingdom and Sardinia. In addition, imported
cases led to secondary infection of medical workers in the United States and Spain but did not spread further. The number of
cases peaked in October 2014 and then began to decline gradually, following the
commitment of substantial international resources.
The high mortality rate associated
with Ebola threatens the ability to perform many interventions that could help
contain the epidemic. Indeed, due to fear of infection, the public were
reluctant to engage in contact tracing (i.e locating persons who has been
exposed to the virus); infected persons are hesitant to present themselves for
treatment; and clinicians are frightened to provide care. In the first year,
between October and November 2014, 72% of all reported patients with EVD were
isolated in Guinea, 20% in Liberia and 13% in Sierra Leone (UNDP, 2014).
In addition, medical staff were
reluctant about treating a highly transmissible infection for which there is no
vaccine, no specific therapy, and a high mortality (death) rate. As a result, a
paucity of knowledge on the disease, combined with the fear produced by the
epidemic, delayed the implementation of simple interventions to prevent deaths
(Fowler et al., 2014).
High mortality rates
recorded fuelled fears surrounding the disease among both medical staff and the
population at large. As awareness of the existence and magnitude of the
epidemic came months too late, the virus had spread considerably.
It is occasionally
transferred to humans through body fluid contact with an infected patient, for
example contact with a cut or scratch on the surface of the skin (Beeching,
2014) and it is also believed that a person can contract the disease only once.
After a 1-21 day incubation period (the time interval from exposure to an
infectious agent to the onset of symptoms of the disease), the Ebola infection can
present symptoms and initiate human-to-human transmission. The widespread
nature of the West African outbreak in 2014-2016 is thought to be related to
the highly mobile communities and dense population within the region.
2. Factors responsible for the Ebola outbreak
Current state of health of a person
can be as a result of five major determinants. This can be represented using
the figure below:
Five social determinant of health (SDOH)
The extent, severity,
and demographic spread of this EVD outbreak have been attributed to various
reasons, including poor health systems, urbanization, high poverty rate, lack
of access to social services and high population mobility, all of which are peculiar
in the three main affected countries (Alexander et al., 2015; Kennedy & Nisbett, 2015; Chan, 2014). All these
reasons surrounds the SDOH illustrated in figure 1 above. However some of the
major factors contributing to the EVD outbreak are as discussed:
2.1 Physical environment
leading to disease transmission
Bats have been
suggested as a possible source for the 2013–2016 Ebola epidemic. Interviews
with the index case (the first case of patients coming to the attention of
health authorities) in Guinea indicated that a two-year old child regularly
played near a tree with colony of insectivorous bats. The species of bats known
to carry Ebola virus were identified close to where the index case lived (Mari et al., 2014).
West Africa is
characterized by a high degree of population movement across exceptionally
porous borders. There is an emerging consensus that the extraordinary magnitude
of the epidemic is basically due to population density and mobility (Kutzin
& Sparkes, 2016). Studies reported that population mobility in these
countries is seven times higher than elsewhere in the world. To a large extent,
poverty drives this mobility as people travel daily looking for work or food. This
population movement created two significant hindrances to the disease control.
First, as noted early on, cross-border contact tracing is difficult.
Populations readily cross porous borders but outbreak responders do not.
Second, as the situation in one country began to improve, it attracted patients
from neighboring countries seeking unoccupied treatment beds, thus reigniting
transmission chains. In other words, as long as one country experienced intense
transmission other countries remained at risk, no matter how strong their own
response measures had been.
families have relatives living in different countries, hence, traditional
custom of returning, often over long distances, to a native village to die and
be buried near ancestors is another dimension of population movement that
carries an especially high transmission risk.
2.2 Poor health services
Guinea, Liberia, and
Sierra Leone, which are among the poorest countries in the world, with recent history
of civil war and unrest that left basic health infrastructures severely damaged
or destroyed and created a cohort of young citizens with little or no
education. Basic infrastructures including road systems, transportation
services, and telecommunications are weak in all three countries, especially in
rural settings. These weaknesses greatly delayed the transportation of patients
to health centres and of samples to laboratories, the communication of alerts,
reports, and calls for help, and public information campaigns.
All three major countries
affected had pre-existing challenges in their health systems with inadequate
infrastructure, severe shortages of trained health workers, shortages of basic
medicines and very weak health information and disease surveillance systems (Dubois
et al., 2015). Liberia, Sierra Leone
and Guinea as at 2013 have 88 496, 79 365 and 24 096 people per health centre
respectively, compared to 10 320 people per health centre in nearby Ghana. In
addition, instead of the recommended one trained health care worker for every
439 people, there was one health worker for 3 472, 5 319 and 1597people
respectively for these three countries. The insignificant workforce was further
diminished by the unprecedented number of health care workers infected during
the outbreaks. Nearly 700 were infected by year end of 2014 and more than half
of them died.
Though the number of
infected health care workers was high at the early state of the outbreaks, but
diminished as proper safety measure was put in place. In Liberia however, as
cases began to decline and the risk was perceived to be lower, stringent
measures for personal protection lapsed. Protective measures in the community,
such as frequent hand hygiene and keeping a safe distance from others, visibly
declined. While in Sierra Leone, exhaustion among staff causes an increase in
loss of health workers.
beliefs and behavioural practices
Cultural beliefs in the three countries have been
similar to what has been seen during previous Ebola outbreaks in equatorial
Africa. New cases of infection arises due to adherence to ancestral funeral and
burial rites. Medical anthropologists have, however, noted that funeral and
burial practices in West Africa are exceptionally high-risk. Data available in August, as reported by Guinea’s Ministry of Health,
indicated that 60% of cases in that country could be linked to traditional
burial and funeral practices. In November 2014, WHO staff in Sierra Leone
estimated that 80% of cases in that country were linked to these practices (WHO,
2015). In Liberia and Sierra Leone,
where burial rites are reinforced by some secret societies, mourners are known
to bathe in or anoint others with rinse water from the washing of corpses. In
some cases, prominent members of these secret societies sleep near a highly
infectious corpse for several nights, believing that doing so allows the transfer
Compassion is another
deep-seated cultural trait: In West Africa, the virus spread through the
networks that bind societies together in a culture that stresses compassionate
care for the ill and ceremonial care for their bodies if they die. Some doctors
are thought to have become infected when they rushed, unprotected, to aid
patients who collapsed in the hospital premises.
In addition, traditional
medicine has a long history in Africa. Even prior to the outbreaks, poor access
to government-run health facilities made traditional medicine or
self-medication the preferred health care option for many, especially the poor.
Many extended cases have been traced to contact with a traditional healer or
herbalist or attendance at their funerals.
resistance, strikes by health care workers
efforts in all three countries was disrupted by community resistance, which has
multiple causes. Fear and misperceptions about an unfamiliar disease have been
well documented by medical anthropologists, who have also addressed the reasons
why many refused to believe that Ebola was real.
People and their ancestors
had been living in the same ecological environment for centuries, hunting the
same wild animals in the same forest areas, and had never before seen a disease
like Ebola. Equally unfamiliar were the response measures, like disinfecting
houses, setting up barriers and fever checks, and the invasion by foreigners
dressed in what looked like spacesuits, who took people to hospitals or
barricaded tent-like wards from which few returned.
A second source of
community resistance arose from the inability of ambulance and burial teams to
respond quickly to calls for help, with bodies sometimes left in the community
for as long as 8 days. The communities will comply with official advice if it
benefits them. They are far less likely to comply if the result, like
uncollected bodies, causes visible harm.
Strikes by hospital staff
and burial teams have further impeded control efforts. Most strikes occurred
after staff were not paid for weeks or months, did not receive promised hazard
pay, or were asked to work under unsafe conditions associated with the deaths
of many colleagues.
face of early and persistent denial that EVD was real, health messages issued
to the public repeatedly emphasized that the disease was extremely serious and
deadly, and had no vaccine, treatment, or cure. These messages had the opposite
effect even though it was intended to promote protective behaviours.
If health care practitioners
declared that no cure to the virus, families preferred to care for their loved
ones at home. In their view, if death is almost inevitable, let this happen as comfortable
as possible at home, amid familiar and well-loved faces. Moreover, when
patients were taken to treatment or quarantine, anxious families often received
little or no information about the patient’s condition, outcome, or even the
place of burial. With time, and as entire households died of the disease,
communities began to understand that keeping patients in homes carried a high
risk for care-givers.
For unknown reasons that
may include the stigma that surrounds this disease, the practice of hiding
patients in homes continued in some areas, even after abundant treatment beds
became available. The great stigma attached to Ebola explains why suspicious
deaths are routinely tested for Ebola. Bodies that test negative can be buried
in the traditional way, and families are freed from ostracism by the community.
2.6 Spread by
international air travel
importation of Ebola into Lagos, Nigeria on 20 July 2014 and Dallas, Texas on
30 September, 2014 marked the first times that the virus entered a new country
via air travellers. These events theoretically placed every city with an
international airport at risk of an imported case.
The imported cases, which
provoked intense media coverage and public anxiety, brought home the reality
that all countries are at some degree of risk as long as intense virus
transmission is occurring anywhere in the world – especially given the
radically increased interdependence and interconnectedness that characterize
2.7 Gender dimension
Guinea provides a good example of
the gender dimension of EVD epidemiology. The epidemic affects more women (53%)
than men (47%), a disparity that could be explained by the role of women within
the family as the primary care giver of the sick and thus more exposed to
infection (UN, 2014). In Liberia, there are more fatality cases among women (55.2%)
than among men (44.2%). While in Sierra Leone, men and women are almost equally
affected; around 50.6% of all confirmed cases were males and 49.4%, females as
at October 2014.
Several factors explain the predominance of women
among the victims. The first factor explains that the gender difference in the
death rate is related to sociological aspects of affected communities. As care
providers, women are more likely to be exposed to the disease transmission vectors
such as vomit or other body fluids of an infected family member. Also, certain traditional
practices and rituals for honoring the deceased that women typically perform
also pose an increased risk.
Because Ebola virus
is spread mainly through contact with the body fluids of symptomatic patients,
transmission can be stopped by a combination of early diagnosis, contact
tracing, patient isolation and care, infection control, and safe burial.
It is therefore very
important that Public health professionals focus on providing adequate education
regarding EVD and transmission not only in Africa but, massively, around the
world. A regular program of communication on disease outbreak from public health
officials is needed and should involve multiple outlets such as radio,
television, and social media platforms. These communications should provide
factual information concerning the management of high risk contagious disease
such as Ebola, tailored to the target population.
Communities should continue to be engaged in addressing the routine
health issues they face, not just during crises. In the long run, efforts need
to focus on equipping local communities with the material and knowledge
resources to respond to Ebola and to help build a surveillance infrastructure
that can inform a stronger post-epidemic local and state governance