Volume 1 (1999/2000)
Issue
1 (March 1999)
Issue
2 (Nov. 1999)
Issue 3 (Dec. 1999)
Issue 4 (Feb. 2000)
Issue 5 (March 2000)
Issue 6 (April 2000)
Issue
7 (May 2000)
Volume 2 (2000/2001)
Issue 1 (Sept. 2000)
Issue 2 (Oct. 2000)
Issue 3 (Jan. 2001)
Issue 4 (March 2001)
Issue 5 (April 2001)
Issue 6 (May 2001)
Volume 3 (2001)
Issue 1 (Sept. 2001)
Issue 2 (Nov. 2001)
Categories
Sport: 1
2 3
Lifestyles: 1 2
3
Commentary: 1 2
3
Review: 1 2
3
Writing: 1 2
3
Event: 1 2
3
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Catherine Howard
Regina Mundi, Cork
One of the greatest threats to mankind these days is a lethal virus.
Some, like HIV, which causes AIDS, have affected the human race greatly.
The full effects of AIDS on the earth's population is not yet known, it
can only be estimated. However, none are as terrifying as the sisters
Ebola and Marburg are. They are members of a family of RNA viruses known
as filoviruses. When magnified with an electron microscope (see photograph
below), the virus particles have the appearance of thin pieces of thread
and are thus referred to as thread viruses or "worms". The most
lethal ones are the three sisters: Ebola Zaire, Ebola Sudan and Maburg.
These viruses have no vaccine and no known cure.
Marburg, although not the most widespread of the three, is perhaps
the most deadly. It has the infectious capability of the common cold and
kills nine out of every ten people it infects. Marburg emerged in 1967,
when it killed seven people in the town of Marburg, Germany. It broke
out in a vaccine factory where they were using the cells of monkeys from
Uganda. In all, 31 people caught the virus before it burnt itself out.
It is much like radiation sickness in that there is substantial hair loss
and massive internal bleeding. It would later emerge in Belgrade, Yugoslavia.
Virologists made Marburg a Level 4 virus. Virus containment (or biocontainment)
is divided into four biosafety levels, based on infectious capability
and potential for harm. Biosafety level 1 is of minimal hazard - Salmonella,
E.Coli, etc. Level 2 is moderate biohazard and includes Hepatitis and
Influenza. Level 3 is of a high biohazard and multiple vaccinations are
required to work within it. Level 3 includes Anthrax, Typhus and HIV.
Level 4 means extreme biohazard. Level 4 laboratories maintain maximum
security. The infectious agents - Ebola and Maburg, Lassa Fever and Hanta,
are all highly virulent and there exists no vaccines or cures.
When working in a level 4 laboratory, you have to wear special clothing
for protection. These are known as "space suits", because they
resemble the suits astronauts have to wear. Oxygen is pumped directly
into the suit, never coming in contact with the contaminated air in the
lab. In theory, they completely protect the person inside the suit from
what lives in the air around them.
There are two types of suits - Chemturion and Racal. Chemturion suits
are blue in colour and are for working in laboratories. When working in
a lab, an air hose is plugged into the suit. Air circulates around the
suit by way of the "blowers". The blowers make a lot of noise
and technicians often have to wear earplugs. Then there is the yellow
or orange Racal suit. These have a battery-operated air supply incorporated
into the suit and are disposable. They are for fieldwork only.
A Level 4 laboratory is kept under constant negative air pressure. This
means that if there is a leak, or something else goes wrong, the contaminated
air would be sucked back into the laboratory instead of to the outside
world. To get into a Level 4 lab, you have to go through an airlock and
a decon (decontamination) shower on the way back out. It is policy for
all work to be done in pairs so that they can each check each other's
suits regularly.
All of the above measures are needed to contain and work safely with Level
4 viruses such as Marburg.
Then, in 1976, came Ebola.
It first emerged in both Sudan and Zaire simultaneously. In a mission
hospital run by Flemish nuns in Yambuku, Zaire, a local schoolteacher
came to the dispensary with what he thought was treatable malaria. The
nurses gave him anti-malaria drugs and sent him home to his wife and young
baby. Three or four days later his fever and muscle pains had progressed
into severe bleeding and excruciating pain. They put him in a bed at the
hospital and hooked him up to an IV. The hospital was understaffed and
did not have adequate medical supplies. They were re-using syringes after
only rinsing them with water. They had no choice but to do so. Therefore
the same needle that was used to treat the sick schoolteacher was used
to treat many other patients at the hospital.
When a person infected with a lethal haemorrhagic fever reaches the final
stages of the disease they haemorrhage and die. Military experts have
a term for this - they say the victim "crashed and bled out".
The schoolteacher crashed and bled out ten days after he first visited
the mission hospital.
Within weeks, the new and uncontrollable disease had devastated the tiny
village of Yambuku. The symptoms and effects of Ebola on humans are terrifying.
For the first six days, the victim experiences back pain and headaches.
They develop a fever and a sore throat. Some mistakenly believe that they
are getting the 'flu'. Clots form in the blood stream, slowing the flow
of blood to the major organs. Some experience what is called "third
spacing" - when the blood fills the space between the skin and the
flesh. As a result of this, red and white blisters appear on the surface
of the skin. From the seventh day onward, the mouth, gums and salivary
glands bleed. The lining of the tongue, throat and trachea either slips
into the lungs or are expelled while the victim is vomiting violently.
The liver dies. The kidneys fail and the blood becomes toxic with urine.
On or after the tenth day, the eyeballs haemorrhage and turn red with
blood. The heart softens and then bleeds into its own chambers. The lining
of the gut is lost. In the last moments of the victim's life, they are
sent into a fit, limbs thrashing wildly, spraying infected blood everywhere.
It is at this time that the virus is trying to find a new host.
Viruses work by first latching themselves onto the wall of a cell, causing
the wall to close around the virus particle and engulf it. Once inside,
the virus particle sheds its outer layer of protein. The core (made of
either DNA or RNA - Ebola is made of RNA) then attacks the cell, reproduces
and then moves onto another cell. In the body, this takes about 25 minutes.
As the people of Yambuku were unaware of the dangers of the virus and
how it was transmitted, many of them stayed with the sick and dying members
of their families, and then went on to prepare the bodies for burial,
as is the custom in that part of the world. Many were infected because
of this.
Virtually unknown to the people of Yambuku, across the river in Nzara,
a similar epidemic was occurring there also.
Several weeks into the crisis, one of the nuns at the Yambuku mission
hospital fell ill. This was a great shock to the nuns - she was the first
white person to become infected with the strange disease. Until then,
it had only posed a threat to the natives of the village. (Unfortunately,
it took the death of a white foreigner to reach for outside help, but
even so it drew attention and help to these hot zones). Very worried,
they put the nurse in one of the few motorised vehicles they had and sent
her on her way to Maridi, where they believed there was a hospital. At
that stage, no one who had become infected had survived.
But Maridi was in the midst of an epidemic also.
It was time to get outside help.
Ebola Virus II
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