By
Mohamoud Ahmed Farah, ATU Master of Science candidate[1].
The current epidemic of Ebola in several West
African countries has been characterized by the World Health Organization (WHO)
as the most serious medical emergency in the modern era. Ebola is a multi-systemic acute febrile viral
infection which is characterized by flu like symptoms such as fever, headache,
myalgia (muscle pain), and abdominal pain, and later vomiting and bleeding.
Ebola, previously known as Ebola Hemorrhagic Fever, is also known as Ebola
Virus Disease or EVD. It is often fatal. The current outbreak of Ebola is
caused by the Ebola virus, the single member of the species Zaire
ebolvirus. There are five species in the
genus Ebolavirus: Zaire ebolavirus, Sudan ebolavirus, Täi Forest ebolavirus,
Bundibugyo ebolavirus and Reston ebolavirus.
The first four species are known to cause Ebola in humans. The fifth, Reston ebolavirus, named for the
town of Reston, Virginia in the US infects primates, but does not cause Ebola
in humans. It may have originated from the Philippines. Ebola was first discovered
in 1976 in an area in Zaire near the Ebola River. It has since caused outbreaks
in the Sudan, Gabon, Democratic Republic of the Congo (DRC), Uganda and Ivory
Coast. The current epidemic is centered
on the three countries of Liberia, Sierra Leone and Guinea, but cases have also
been seen in Nigeria, Senegal, the United States, and Spain, and most recently
in Mali. There is also a lesser known
and unrelated outbreak of Ebola in Boende, Equateur in the DRC, but this
outbreak appears to have been stopped.
Ebolviruses belong
to the virus family Filoviridae which
is part of the order Mononegovirales.
Other members of the Filoviridae are
the Marburg virus and the Cuevavirus.
Marburg virus, which also causes hemorrhagic fever, was first described
in central Europe in 1967 and has also been seen in central and southern
Africa. Cuevavirus, a more recent
discovery, found in the Lioviu cave in Spain, is not known to cause human
disease. It is endemic in Spain, France
and Portugal.
Ebola is highly contagious and lethal. WHO considers it a Select Agent Risk Group 4,
which requires the highest level of biosafety (Biosafety Level 4 or BL-4); some
countries consider it a bioterrorism agent.
Transmission of Ebola
The primary animal host of Ebola virus has not
been definitively proven, but fruit bats are thought to be the natural host.
Humans can be infected by contact with body secretions, blood or organs of
infected animals such as bats, monkeys, chimpanzees, antelope or gorillas. Once Ebola jumps to humans, it can spread via
direct contact with blood or bodily secretions of an infected and symptomatic
person through skin cuts or wounds and via contact with the mucous
membrane. Bedding and clothing
contaminated by fluids of infected individuals are also a source of
transmission.
Health care workers and close relatives of the
infected who are most likely to come in contact with infected material are at
the highest risk for infection. People
who work at burial sites and funeral homes are also at an enhanced risk.
The incubation period of Ebola virus is
between 2 and 21 days. Infected people
can transmit the virus once symptoms of the illness appear. They remain infectious as long as their body
fluids including breast milk and semen contain the virus. Men who recover from the virus may have the
virus in their semen for up to 7 weeks after they recover from the illness.
Outbreaks of Ebola start with a single patient
or a patient zero. According to a report
in the New England Journal of Medicine, patient zero in the current epidemic
may have been a 2-year old who died on December 6, 2013 just 4 days after
showing Ebola symptoms in a village in Guinea near the border with Sierra
Leone. Soon after, several members of
his family including his mother, sister and grandmother became ill and
died. Ebola then broke out of the
village via people who may have attended the funerals for the deceased.
Fatality Rate of Ebola and the Current Epidemic
Ebola has a high mortality rate. In some past outbreaks, 90% of infected individuals
succumbed to the illness, but a 25% case fatality has also been seen. The current epidemic is the most extensive
and so far approximately 50% of the nearly 10,000 people infected (almost all
in West Africa) have died.
Extent of the Current Epidemic
According to WHO, as of October 23, 2014, 9966
people have been infected and 4881 have died of Ebola. Almost all the cases are
in Liberia, Sierra Leone and Guinea. All
three countries have been through recent wars and have poor health care
infrastructure. One acutely ill person
who flew to Nigeria from Liberia led to the infection of 20 people in Nigeria. Upon confirmation of the infection, Nigerian
heath authorities quickly activated an Ebola Incident Management Center. The center identified 894 contacts of the
index patient. Twenty patients were
confirmed to have been infected as the result of this incident, eight of whom
later died of Ebola. In Senegal an infected person travelled over land from
Guinea. The patient was successfully treated. Both Nigeria and Senegal appear to have
stopped further spread following rigorous case detection control measures and
both countries have now been declared free of Ebola by WHO.
On 24 October 2014, Mali announced that a
young girl whose mother died of Ebola in neighboring Guinea and who was brought
to Mali by relatives is suffering from Ebola.
Health authorities in Mali indicate that the child was quickly diagnosed
and immediately place in hospital isolation and that people who have had
contact with the infected child are either in isolation or being closely
monitored. The child succumbed to the
illness on 25 October. Later reports
indicate that the child was brought to Mali in a bus and had travelled for more
than 1000 km while symptomatic. Once in
Bamako, the child was first treated for typhoid and only later tested for
Ebola. Forty-three people have so far
been identified for the possibility of high risk exposure. Mali lies next to Guinea, one of the
countries at the epicenter of the epidemic.
Mali, which is going through a rebel insurgency, has very few health
care workers for a population of more than 12 million. According to the Malian Ministry of Health,
Mali has allocated 672,000 US dollars to combat the spread of the disease and
has created 10 hospital isolation wards for treatment.
Cases in Europe
Two Spanish missionaries in West Africa became
infected and were evacuated to Spain. An
assistant nurse who took care of both patients (who later died) became infected
and is currently hospitalized. Some of
her contacts are quarantined and others are being closely monitored, but so far
none of them have shown symptoms of Ebola.
Cases in the United States
Three American health care workers were
infected in West Africa and were medically evacuated to US hospitals. All three survived and are now virus
free.
A Liberian man who travelled from Liberia by
air was diagnosed with Ebola soon upon his arrival in the state of Texas and
later died of Ebola. Two nurses who
assisted in his treatment became infected and are being treated in specialist
hospitals in the US. None of the other
contacts of the patient have been infected and 44 of them have been declared
virus free and are no longer monitored, but health care workers who treated the
patient or people who have been in contact with the infected two nurses are
being monitored. Monitored individuals
include some passengers of two airlines one of the nurses travelled in prior to
her showing clear symptoms of the infection.
On October 24, one of the nurses who contracted Ebola after treating the
Liberian patient, was declared virus free and has been released without
movement restrictions. Few hours after
being released from the hospital, the President of the United States Baraka
Obama met her at the White House ostensibly to calm public fear and remove the
stigma that could be attached to this infection.
A cameraman working in Liberia for the US TV
news outlet NBC became infected and was evacuated to a US hospital. His co-workers who also returned to the US
have been quarantined. In addition, on
23 October, a hospital in New York City announced that there has been a
positive diagnosis of Ebola in a doctor who worked in West Africa for the NGO
Medicines sans frontiers. The doctor is
being treated and health authorities indicate that the risk posed by this
patient is minimal since he was admitted to the hospital as soon as he
developed initial symptoms. Three of his
contacts are under voluntary quarantine.
Stopping the Epidemic
The current epidemic is the most wide
spread. Past outbreaks have occurred in
remote rural areas, but this epidemic has spread to heavily-populated urban
centers. Few cases have been identified
in Europe and the United States, but these regions have the resources and the
health care infrastructure to limit the spread of the virus. The biggest concern is that the virus may
breakout of the three stricken West African countries to the neighboring
region. Many countries in the region
have the same ecosystem and health care infrastructure inadequacies as the
three affected countries. However, the fact that Nigeria and Senegal have been
able to deal with the first cases of Ebola to reach them is an encouraging
sign.
There is no cure for Ebola. Two vaccines are currently being fast-tracked
through human trials. If these vaccines prove effective, they will first be
giving to health care workers in West Africa. There are no known effective
antiviral drugs for Ebola. ZMapp, an
antiviral drug in clinical investigation trials, has been rushed to treat
several patients, but supplies of ZMapp quickly ran out as only enough had been
made for investigations and not for treatment.
Another drug brincidofovir has also been used in a patient in Texas who
did not survive the infection.
With respect to treatment, there are some
encouraging signs. US hospitals have
been able to successfully treat 5 patients.
Spanish doctors have also been able to treat the first person infected
in Spain. The recovery from the infection of these patients is currently
attributed to the supportive care available at the medical facilities in the US
and Spain. While not definitive, there are indications that patients who have
recovered from an Ebola infection have transferable antibodies that may be used
to help in treatment. Whether some
people recovering from the infection develop long lasting immunity awaits more
research and data.
International health authorities indicate that
it may take 4 to 6 months to bring the current epidemic under control. At the present time, the spread of the
infection is exponential with some predictive models suggesting that as many as
1 million people may become infected in West Africa by early next year if the
epidemic is not quickly brought under control.
What Steps Should Somaliland Take to Protect its Citizens from the
Spread of Ebola?
Somaliland should be considered a low risk
country. Somaliland has no trade or
other links with the affected countries of West Africa and the chance of direct
transmission is minimal. So far no cases
have appeared in the Horn of Africa region countries with which Somaliland has
a contiguous border. In the Horn of Africa,
the two countries of Kenya and Ethiopia are major travel and tourist
destinations. Many international
organizations have substantial presence in both Kenya and Ethiopia. Kenya and Ethiopia are also major commercial
centers and receive large numbers of travelers from all over the world. Both countries have stopped direct airline
travel to the stricken countries in West Africa. So far no cases have been seen in these two
countries.
Somalia has large number of African
peacekeeping soldiers some of whom come from West Africa. The African Mission
in Somalia (AMISOM) has indicated that it will no longer bring new soldiers
from the Ebola-affected countries.
The probability of someone travelling from the
stricken countries bringing Ebola to Somaliland is low. However, at the present
time, Somaliland does not have adequate health care infrastructure for
detection and case control. Somaliland
authorities and local WHO officials have indicated that they are working hard to
put control measures in place as soon as possible and that an epidemic control
unit has been created.
A key in stopping transmission of Ebola is the
quick diagnosis of infected people and effective isolation. Health care workers
treating patients are at heightened risk and must be provided with proper protective
equipment and clothing. Somaliland
authorities should create an Ebola Incident Emergency Unit with trained
personal and hospital isolation wards.
All health care workers must receive Ebola specific infection control
information. Health care staff at
ambulatory care centers, including private clinics, must be trained to
recognize Ebola symptoms and instructed on how to deal with suspicious cases.
Identification of all contacts or contact
tracing is essential for an effective control of infectious diseases outbreaks.
Contact tracing requires full community participation and health authorities must
provide the public with complete and correct information in a manner that does
not create panic. Public health
authorities must begin a proper education campaign to make sure that people
have the right information and confidence in the system. It is important for
the public to avoid superstitions and the pursuit of unproven remedies outside
of the health care setting. Health
authorities and the media must work hard to remove any stigma associated with
the infection to ward off against patients going underground and spreading the
infection further in untraceable manner.
The steps Senegal and Nigeria took are good examples of what Somaliland
should do to protect its citizens from Ebola. These examples indicate that it
is possible to counter this epidemic effectively when the public health system
is vigilant, ready and well-prepared with the right tools.
[1]
Mohamoud Ahmed Farah is a Master’s Degree candidate at ATU’s Biomedical Science
Department. He is currently preparing a
chronicle of parasitic diseases common in Somaliland. He works under the supervision of Dr. Ahmed
Hussein Esa.
