Several years ago, a virus which originated in Africa swept the entire world
killing millions. This virus is the commonly known HIV virus, the virus which
causes the fatal AIDS disease. In the 1950's after virologists began the
classification of viruses, isolated cases of what are called "hot
viruses" began springing up around the world. Most of the deadly viruses
were hemorrhagic fever viruses. Some different forms of hemorrhagic viruses are
Hantaviruses, Arenaviruses, Flaviviruses, Bunyaviruses, and one of the most
dangerous types of viruses, the filovirus. If one of these viruses, especially a
filovirus such as Ebola, were to mutate it could concievalby be the end human
existance on the planet. The first of the filoviruses was seen around 1967,
identified as Marburg. It killed seven laboratory workers in Germany who were
handling monkey blood. The next major filovirus emersion was in 1976. This virus
was a more severe virus, Ebola Sudan. It swept across N'zara and Maridi in
Sudan. That same year, a strand of Ebola called Ebola Zaire, killed nearly
three-hundred people in Yambuku, Zaire. In 1976 Sudan was again hit by Ebola
Sudan. More recently, in 1995 Ebola killed more than 200 people in Zaire.
Surprisingly, Ebola has reached the United States before. In 1989, Ebola
surfaced in a monkey house in Reston, Virginia. The strand of Ebola was called
Ebola Reston. It seemed to be airborne, yet harmless to humans. This strain of
Ebola was brought to the United States through the trading of monkeys for
scientific purposes. (Johnson, as cited in Le Guenno,1995) Although it may not
look like Ebola has done a lot of damage to the human race, take into
consideration all of the viruses which are slightly less deadly than Ebola.
Arenaviruses alone have killed more than one-hundred fifty people throughout the
world in the last forty years. In two outbreaks, Rift Valley Fever, a Bunyavirus,
infected nearly a quarter of a million people and 1000 of those infected died.
Flaviruses and Hantaviruses have swept across most of Asia infecting millions of
people for the last one-thousand years. It should be apparent that these viruses
spread easier than Ebola but are not as deadly. Therefore, if one of these
viruses was to mutate into a virus with a mortality rate similar to Ebola, it
could put a dent in society. (Johnson, 1995) Currently Ebola is transmitted by
contact with bodily fluids from an infected victim. For example, a doctor by the
name of Sheth Musoke who worked in a Nairobi hospital in 1980, contracted
Marburg when he was splashed with blood and vomit from a dying victim of Marburg.
He was lucky enough to survive his ordeal with Marburg, for Marburg only has a
twenty-five percent mortality rate. Most outbreaks of hemmorahagic fever viruses
are triggered by the disruption of nature. For instance, in 1989, in a small
Venezualian community cleared a forest to make way for more housing and
commercial space. Within weeks Guarnarito, a Arenavirus, infected nearly
one-hundred people in the town due to a fine dust of contaminated wood which
settled over the town. Although most damage to the environment is brought on by
humans, in 1993, after heavy snowfall and torrential rains Sin Nombre, a
Hantavirus, broke out in New Mexico, Colorado, and Nevada. With the extra rain
and snow, grain crops flourished, but along with the grain came the deer mouse,
a natural host of Sin Nombre. Sin Nombre infected one-hundred forteen people and
killed fifty-eight. Some Hemorrhagic Fever viruses, mainly Bunyaviruses, are
carried by mosquitoes. If a dam is built and the water level rises mosquito
populations flourish. The action of damming a river caused an outbreak of Rift
Valley fever, in 1970. Nearly 600 people died in that outbreak, and almost all
of them were bitten by mosquitoes. It is not likely for Ebola to become
transmitted by mosquitoes for they do not contain the appropriate proteins for
Ebola to flourish. Also, if a mosquito was infected with Ebola it would die
within hours due to its small size. So far Ebola has mutated into many different
strains. Originally Ebola mutated from Marburg, another filovirus. From Ebola
came Ebola Zaire, then Ebola Sudan, and finally Ebola Reston. Ebola is prone to
mutate in the near future because the replication process from cell to cell
happens so quickly. When a virus replicates itself, the virus first unwraps
itself sorting its seven proteins and its RNA. Then the replication protein
starts its job. This protein is dependent on RNA for copying cells. The RNA uses
a sort of template to write each of the genes into another RNA message which
then tells the host cell to synthesize a specific viral protein. After the cell
has made the seven different needed proteins, the RNA copies the entire strand
of proteins creating an entire template for a viral cell. New genes are then
produced, and proteins wrap themselves around the genes. Then the new viral cell
immediately leaves the host cell. (Crusberg and Crowley, 1995) Unlike other
viruses, Ebola does not sit around in the host cell swapping chromosomes until
each viral cell has the appropriate chromosomes. Instead, Ebola immediately
leaves the cell. Compared to other viruses Ebola is roughing the duplication
process so that it can duplicate itself nearly twice as fast. Since the
replication process happens so fast the RNA does not have a chance to check the
new viral cell it has made; it simply sends the new viral cell off to infect
other cells. If the RNA has made a mistake on one single strand of protein the
virus could be changed immensely, causing a new strain of the virus. (Crusberg
and Crowley, 1995) Every different virus has different proteins and replicates
itself differently. When looked at under an electron microscope the viruses vary
greatly in appearance. Many viruses are named for their shape as seen under a
microscope. For instance filoviruses were named becuase of their filamentous
apperance. Such as: Ebola, filovirus Lassa, arenavirus Encephalitis, hantavirus
Yellow fever, flavivirus If a change made the virus airborne, the world
population could be decimated. Ebola could then be transported through the air.
If one person in Africa was infected with the virus and he got onto a plane
flying to America, he would most likely infect every passenger and crew member
on the plane. The people on the plane would not realize they were infected for
several days. The infected people would then walk through the airport infecting
nearly every person they passed. The people in the airport who caught the virus
from the original plane of people would then get onto planes going to many
different locations throughout the world. Each infected person who got onto a
different plane would in turn infect nearly the entire plane. If a flight's
destination was France, a plane full of people infected with Ebola would be
traveling throughout France infecting every person they either talked to or
breathed on. If this process was to continue worldwide, the well being of every
person in the world would be jeopardized due to one single person.
Hypothetically speaking, if the virus was to reach all corners of the earth
infecting every person as it went, the world's population would drop to a mere
500- million, but the virus would still be lurking among the surviving waiting
to strike again. If it was to strike again in the same intensity the world
population would decrease to 50 million. It should now be apparent that if Ebola
or a similar virus was to mutate into an airborne virus the entire population of
the world would be at risk. In the past, many have died from similar viruses and
it is probable that as our population continues to grow and we disrupt nature by
deforestation and similar activities a more lethal virus will emerge. It is
possible that Ebola and other viruses are just a warning from Mother Nature that
we are overstepping our boundaries and we are not the most powerful force on the
planet. Addendum: On December twelvth in Liberia the New York times reported
that four people who had close contact with a man who caried the Ebola virus had
broken out with symptoms of Ebola. They believe this could be the start of a new
outbreak. Is this the beginning---of the end?
Bibliography
Axton, Miles (1995). Regulations of a Runaway Replicator. Netscape, Address
Unknown. Pages 1 and 2. Crowley-John,B.S and Crusberg-Ted,PhD (1995). Ebola and
Marburg Viruses: Genomic Structure, Comparitive and Moleculare Biology.
Netscape, Address Unknown. Pages 1 and 2. Author Unknown(1995). Emerging and
Re-Emerging Viruses: An Essay. Netscape, Adress Unknown. Pages 1-3. Le Guenno,
B.(1995, October). Emerging Viruses. Scientific American, pp. 56-64.