The Ebola
Virus
At some
point in your life you may have a disease.It may be relatively harmless
or it may be quite serious.Disease is a sickness of the body or
mind.There are thousands of diseases that can strike almost every part of the
body.Some diseases are chronic (lasting a long time);while others are called
acute,occuring in short,sharp attacks.There are many different causes of
disease.Harmful micro organisms can invade the body and cause infectious disease.Infectious diseases are the only
ones that can spread from person to person.Most are micro scopic organisms
called bacteria and viruses that invade the body.Poor living conditions can
also cause disease.Some diseases occur at birth.:others may be passed from
parent to child.The reasons for some diseases are unclear,as a result,scientist
are constantly working to understand the causes of diseases and find possible
cures.
Africa was long characterized as the “dark
continent,”impentrable,disease ridden,and dangerous.To many Europeans,Africans
personified suffering,and their enviroment seemed a housefull of fever and
affliction.Europeans had good reason to connect Africa with disease.For
centuries,their attempts to penetrate the coast of the continent has been
effectivly frustrated by disease,against which they had little or no
resistance.With high mortality rates,it is no surprise that Europeans called
Africans “the white mans grave,”and believed that Africa was more disease
ridden than other parts of the world.In fact many people continue to think that
Tropical Africa has a well deserved reputation
as a breeding ground for dozens of diseases.
“Africa is a sick continent,full of sick
and....starving people.”(Prins.1989)This view has been proved by scientific
speculation concerning the appearance of so - called exotic diseases like
Ebola,Marburg,and Lassa fevers.Recent technological advances espeically in
electron microscopy,molecular biology,genetics,and immunology have scientists making important new
discoveries that is hoped to -lead to lead to cures for viral infections to
equal those available for bacterial,fungai,and parasital infection.However the
identification of Africa as the home of “exotic new diseases” has reinforced
the widespread views of that continent as a major source of disease causing
germs.
Textbooks on tropical diseases in Africa
are well out of date.With the recognition of new and deadly viral
infections,the classical descriptions of major diseases such as Malaria and
Yellow Fever must be thoroughly revised.After the appearance of the Marburg
virus in 1967 and the Lassa virus in 1969,the Ebola virus in 1976 provoked a
violent disturbance.The Ebola story beganwith almost contemporaneous outbreaks
of a deadly infection in Maridi region of southern Sudan and in the Bumba Zone
of the equator region of North Central Zaire,neighboring on the Sudan,and the
towns on the couse of the Ebola river.The Ebola virus is responsible for severe
and often fatal hemorrhagic fever.The Ebola virus is named after the river in
Zaire.The epidemic of the Ebola virus emerged in June 1976,with an index case
in Nzara,Southern Sudan,among workers in a cotton factory.A patient went to a
large hospital in Maridi,where the disease spread rapidly among the patients and staff.
The epidemic ran it’s path by Nov.1976.There were 148 deaths in 284 detected
cases (52% mortality).In 1979 a further outbreak occured in Southern Sudan.The
epidemic in Zaire was traced to an index case on September 1,1976.A total
of 318 cases occured with 288 deaths
(90.5% mortality).Several patients and members of the hospital
staff,physicians,and attendants died also.The epidemic had terminated by
Nov.5,1976.Fatalities occured in a hospital in Kinshasa in the cases,of three
nurses who had been transfered from the infected area,and it became clear,that
the passage of the virus from human to human had occured through the
contamination of needles and suringes.Ebola can be transmitted through contact with instant
blood,semen,body fluids,and possibly respiratory secretions.The virus has been
detected in the organs of patients with recovery from the fever.Unsanitary
conditions and lack of adequate medical supplies has been a factor in the
spread of disease.Epidemiologist have been active in trying to trace the
origins of the Ebola virus and the distribution of the infection throughout
Africa,locate the host other than humans,as well as learn methods of
transmissions to humans and the ways the virus is maintained and bred in
nature.
The Ebola virus seems to have a window
period of 4 to 16 days,after which time the impact is unbearable.The onset is
sudden and harsh.The patient developes fever,severe head and muscle ashes and
loss of appetite.The next stage involves diseminated intravascular coagulation
a condition characterized by both blood and hemorrhaging.The clots usually form
in vital internal organs such as the liver,spleen,brain,forcing capillaries to
bleed into surrounding tissue.Other symptons include nausea,vomiting,and
diarrhea with blood and
mucus,conjunctivitis,and sore throat soon follow.A rash appers on the trunk and
quickly covers the rest of the body.The patient is than harrassed by
spontaneaous bleeding from all body outlets,coupled with shock and kidney
failure and often death within 8 to 17 days.
The epidemics in Sudan and Zaire
terminated as abruptly as they started.However,in 1979 another hospital
outbreak occured in Tandala,Zaire,300 KM distance from the original Bumba
outbreak.Through the 1980’s,no further outbreaks have been reported in
Sudan,Zaire or elsewhere in Africa.self-satisfaction was shattered in the
United States and internationally in early November 1989 when an
epidemic,confirmed to be caused by the Ebola virus,burst in a shipment of 100
Macaca cynomalyus monkey originating in the Phillipines and shipped to a
laboratory in Virginia.Sixty of the one hundred monkeys died. A devastating
outbreak among humans took place again in 1795 in Kirkwit.500km east of
Kinshasa,Zaire;the disease claimed 244 patients out of 315 reported cases.It is
interesting to note that the epidemic ended within a few months,as suddenly as
it began;this puzzled scientist,who are still unaware of the causes and nature
of this so called hot virus.Despite the dreadful speed with which the disease
killed it’s victims,scientists were happy that they contained it with
relatively small number of fatalities.Recently obtained historical
documentation suggests the possibility that the Athenian plague at the
beginning of the Peloponneian War around 430 b.c. should be attributed to the
Ebola virus.
The Ebola virus is classified as a
ribonucleic acid virus and is closely related to the Marburg virus,first
discovered in 1967.The Marburg and Ebola viruses make up only two members of
the Filoviridae family,which was first established in 1987.Electron microscope
studies show the Ebola virus as long filaments,650 to 14000 nanometers in
length,that are often either branched or intertwined.It is believed that once
in the body, the virus produces proteins that suppress the organisms immune
system.This allows it to reproduce.There appears to be no known or standard
treatment for Ebola fever.No chemotherapeutic or immunization strategies are
available,and no antiviral drug has been shown to provide positive results.Plasmapheris
with plasma from recovered patients has been tried as treatment.Interpretation
of limited trials indicates little hope of an effective therapy.No drugs have
been effective.A possible vaccine remains a dream.It should be emphasized that
most of the Ebola patients who came to a clinic or a hospital had had several
days of treatment with an antimalarial drug,often followed by typhoid treatment
or antibiotics of whatever kind available.There is no known treatment for Ebola
fever.
The puzzling characteristics of the Ebola
virus are the location of it’s primary natural resovoir,it’s sudden explosion
and the unknown reason for it’s quick end and the unusual discovery of the
virus in the organs of people who have survived it.In the past,experimental
work on the virus has been slow because of it’s high pathogenecity.In 1995 the
World Health Organization investigators and epidemiologist captured about three
thousand birds,rodents,and other animals and insects that are suspected of
spreading the disease,in order to investigate the source of the
virus.However,the results,were dim and inconclusive.The main facts about the
disease are still a mystery,with the exception of the established tie between
primates and Ebola virus infection in humans.
This conclusion was reached after the
fatal infection of a french researcher in Ivory Coast who performed an autopsy
on a chimpanzee that had died from a disease with the same symptons as the
Ebola fever.Yet the human outbreaks in Zaire and Sudan have not been traced to
monkeys.As long as the -perplexing questions linger,the disease should be
contained,with specific emphasis on the improvement of sanitary conditions and
the control of body fluids contact.