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Someone once said that the truth is sometimes stranger than fiction. This is not
surprising because the author of fiction must maintain some level of credibility with his
reader and is thereby limited in what he can say. Reality has no such limitations, as
evidenced by the following article, which is a more terrifying and diabolical story than
most fiction authors would ever dream of creating.
The following is a news clip taken from the 1996 update to the Funk and Wagnalls
encyclopedia.
Ebola Outbreak Vexes Zaire
August 95
The spread of the deadly Ebola virus infection, an illness with no known vaccine or
cure, continued in Zaire into the summer months, after a brief lull in May that had led
health officials to mistakenly believe the virus was under control. Since mid-April, when
doctors and nurses performed emergency surgeries on a 36-year-old man who had been
infected with Ebola, the virus had claimed the lives of more than 200 people in the city
of Kikwit and its outlying villages.
The man, a hospital technician whose job was to draw blood samples, died soon after his
operations. Not long afterward, the doctors and nuns who had treated him became infected
with the virus themselves. Initially, they experienced flulike symptoms: headaches, high
fever, and diarrhea. But unlike persons experiencing the flu or a common cold, within a
few more days they were vomiting a thick black substance-the highly contagious,
virus-infected remains of their internal tissues. Soon they, like the initial victim,
began to bleed massively from every orifice of their bodies, and then they died.
In mid-May, a team of international doctors and virologists arrived in Kikwit, a city
with an estimated population of about 400,000, located about 400 km (250 mi) from
Kinshasa, the capital of Zaire. By then, the virus had already raged throughout the
hospital and had killed or infected most of the staff and patients. Those who had not
fallen victim to the virus had fled the hospital in terror. Many who fled had unknowingly
been infected with the virus, which has an incubation period of anywhere from 2 to 21
days, and they carried the virus with them.
Armed with sterilized needles and other sanitized hospital supplies and medical
equipment, the team of health experts moved quickly to try to contain the outbreak and to
educate the citizens of Kikwit about the nature and transmission of Ebola. Until this
outbreak, the virus had not been seen among humans for 16 years. Like human
immunodeficiency virus (HIV), the virus that causes acquired immune deficiency syndrome
(AIDS), Ebola can only be transmitted through direct contact with the blood or bodily
fluids of an infected individual. Ebola virus does not travel through the air. According
to health experts, within days of the initial symptoms, Ebola virus attacks an
individual's immune system and can destroy the body's soft tissues, including the liver,
heart, and brain. After the first symptoms appear, the virus takes about a week to run its
course. The only internal body parts the virus cannot destroy are muscle and bone.
Ebola was first identified in Zaire in 1976 and has resurfaced three times among humans
in central Africa. In all four outbreaks, the main victims were doctors, medical staff,
and patients exposed to the virus through unsanitary hospital conditions. Many hospitals
in the impoverished region of central Africa lack fresh water, rubber gloves, gowns, and
other sanitized supplies that can prevent the transmission of disease. Also, it is not
uncommon for hospital workers in the region to use the same needle when drawing blood from
different patients, further facilitating the spread of Ebola and other blood-borne
diseases. Hospitals in central Africa are overcrowded, and often several patients share a
single bed, which can consist of a soiled mattress lying on the floor. During the outbreak
in Kikwit, where it is common practice to wash the body of a dead relative before burial,
many family members of victims unknowingly contracted the virus.
The first reported cases of Ebola surfaced in Zaire and the Sudan. The virus was named
after the Ebola River in Zaire, where in 1976 the virus spread to more than 55 villages
located along the river's edge after an initial outbreak in the city of Yambuku. Soon
after, the virus appeared in the western Sudanese cities of Nzara and Maridi. These early
occurrences resulted in more than 500 cases of Ebola and more than 400 deaths. Before the
May 1995 epidemic in Kikwit, the last outbreak of Ebola virus among humans occurred in
Nzara, Sudan, in 1979. Of the 34 cases reported at that time, 22 resulted in death.
Despite 16 years of scientific research and field investigations, the origin of the
Ebola virus remains a mystery. Researchers do know that Ebola is made up of seven proteins
that surround a piece of genetically encoded material, but they know little about the
inner workings of the virus. From Ebola's structure, scientists suspect it may be an
ancient organism. In addition, Ebola and a related virus, called Marburg, are the only
known filoviruses in the world. Under a microscope, most viruses are round in appearance,
but filoviruses form long, curly, ropelike shapes.
Ebola and Marburg, along with certain other viruses, cause hemorrhagic fevers. All
illnesses caused by hemorrhagic fever viruses begin with fever and muscle aches. Some of
these viruses eventually cause massive internal bleeding, kidney and liver failure,
respiratory problems, shock, and even death. However, not all hemorrhagic fever viruses
are deadly, and the illnesses caused by some types never progress beyond mild flulike
symptoms. No other known hemorrhagic fever virus causes as much bleeding as Ebola.
Most hemorrhagic fever viruses live in host organisms such as rodents or insects. Some
of the viruses can jump to a new species when they come in contact with other populations
of animals, such as monkeys or humans. Since the first reported cases of Ebola,
investigators have tested the blood of thousands of mammals and insects captured near the
sites of the initial African outbreak in an attempt to isolate the virus's host organism.
Their attempts have been unsuccessful, and the source of the virus or where it circulates
in between outbreaks is unknown.
Scientists have identified four different strains of Ebola virus: Zaire, Sudan, Reston,
and Tai. Virus strains are usually named after the place where they were first discovered.
Ebola Zaire is the deadliest known strain of the virus. With a fatality rate as high as 90
percent, it attacks every organ and tissue in the human body, except muscle and bone. It
creates blood hemorrhages under the skin, dissolves connective tissue, and destroys the
brain. According to researchers, the virus in the Kikwit outbreak is Ebola Zaire,
virtually identical in structure to the strain seen nearly 20 years ago during the initial
outbreak along the Ebola River. This similarity is an unusual phenomenon, since viruses
are unstable organisms that usually mutate over time-some become weaker, while others
become more virulent. The main difference between the two outbreaks of Ebola Zaire is that
the strain responsible for the outbreak in Kikwit has an average incubation period of four
days, while 20 years ago the virus had an average incubation period of seven days.
Ebola Sudan, while still extremely lethal, is half as strong as Ebola Zaire. Ebola
Reston was named after a 1989 outbreak that occurred among monkeys imported to the United
States from the Philippines and housed in a facility in Reston, Virginia, just outside
Washington, D.C. All the imported monkeys tested positive for Ebola and either hemorrhaged
to death or were sacrificed during a covert operation by federal health officials to
control the virus. The Reston strain of Ebola was not lethal to any of the humans exposed
to it.
In November 1994 a new strain of Ebola virus, known as Ebola Tai, was discovered. The
new strain was named after the Tai Forest in the western African republic of Cote
d'Ivoire, where it was found. A Swiss zoologist developed symptoms of hemorrhagic fever
after performing an autopsy on an infected chimpanzee. She was flown to a hospital in
Switzerland, where she soon recovered. Blood samples and other immunological tests
confirmed that she had come down with a new strain of Ebola. The zoologist had been part
of a team of scientists sent to the Tai Forest to study a band of chimpanzees that had
been dying of hemorrhagic fevers. None of her colleagues from the expedition had been
infected with the new strain of Ebola. The case marked the first time that a human Ebola
infection was directly linked to wild African monkeys.
Despite the extremely high fatality rate of certain strains of Ebola, health officials
maintain that, under sanitary conditions, the virus is actually difficult to contract.
Like HIV, Ebola spreads through direct contact with an infected person's blood or bodily
fluids. Unlike HIV, which can live inside an individual and be passed along to others for
ten years or more before symptoms appear, Ebola has a relatively short incubation period.
Once the symptoms of Ebola appear, precautions can be taken to halt its spread to others.
Health officials say that because Ebola kills its victims so quickly, the chance of the
virus ever becoming widespread among human populations is low.
Like all viruses, Ebola needs a constant supply of host organisms to survive and
propagate. Outside of a host organism, viruses survive as inert genetic material encircled
by a shell of proteins waiting to be activated. Inside a host organism, however, viruses
become active and are able to attach to or inject their genetic material into the host's
cells. The virus's genetic material redirects the cell to produce more viruses. The newly
created virus cells are then capable of infecting other cells. During the replication
process the virus usually destroys the host cell. Scientists hypothesize that apart from
occasional human outbreaks, Ebola survives among a population of wild animals and then
jumps species when a human comes in contact with the virus's host organism. Scientists do
not know specifically where the virus lives between outbreaks.
Ebola is one of several types of deadly viruses detected over the last 25 years. Other
lethal African viruses that have emerged among human populations during the late 20th
century include Marburg, Lassa, Rift Valley Fever, and HIV. Seven out of 31 people died in
1967 after being infected with Marburg virus by Ugandan green monkeys. Marburg is closely
related to Ebola, although it is far less deadly. Lassa, another hemorrhagic fever virus,
infects 200,000 to 400,000 annually in West Africa. Approximately 5000 of those infected
die from the disease. Rift Valley Fever, a mosquito-borne virus, reached epidemic
proportions when it infected more than 10,000 people along Egypt's Nile River Delta in
1977. The virus was first detected in Kenya in the 1950s. HIV is perhaps the most deadly
virus, believed by health experts to have originated on the African continent. Since its
emergence during the 1970s, HIV has infected more than 13 million people worldwide, and
experts expect that number to climb to 40 million by the year 2000.
In addition to Africa, outbreaks of newly reported lethal viruses have appeared in
North America, South America, Asia, Australia, and Europe. Scientists note that the
emergence of these deadly viruses, in most cases, coincides with the recent encroachment
of human beings on tropical rain forests and once-isolated rural villages. Experts believe
that the original hosts of these deadly viruses are somewhere in these areas. Health
experts hypothesize that newly built roadways connecting urban centers with small villages
in western and central Africa, the development over the last few decades in tropical rain
forests, the advent of jet travel, large-scale farming, and a massive trend toward
urbanization have facilitated the spread of these previously unknown viruses among human
populations.
Tropical Diseases
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