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Charlie Minchenberg
Health per. 5
10-13-04
Ebola
The dreaded Ebola virus, named after a river in Africa. Once Zaire, now the Democratic Republic of the Congo. The Ebola
virus is classified under what scientists would call an RNA virus. Viruses classified as RNA, short for ribonucleic acid,
viruses are more scientifically known as the Filoviridae. Ebola as well as Marburg are the two general types of Filoviridae.
Within each there are many different types. Ebola has four identified subtypes: Ebola-Zaire, Ebola-Sudan, Ebola-Ivory Coast,
and the one form that does not effect humans, Ebola- Reston, it has only caused disease in nonhuman primates.
Researchers have come to believe that the virus is animal borne or zoonotic. It is also native to the African continent
and is always maintained in an animal host.
On August 24, 1996 the World Health Organization announced the end to the tragic 1995 epidemic. They deduced this by letting
three full incubation periods of the virus, which is three weeks go by. In that time a new case did not appear. During the
time from first outbreak to last some 315 known victims were diagnosed, 244 or 77 percent of whom had died. This is a frightening
number. In comparison to, the 1918 influenza epidemic, 20 million people died, out of the more than a billion sick. The Zaire
strain of the Ebola virus luckily, although devastating with its short incubation period and catastrophic symptoms to those
who fall victim to it, is fairly easy to contain. This strain of the virus is very hard to transmit. To do so it would require
either exposure to infected blood products or very close contact with a sick individual.
Before it emerges, the virus may be undetectable for millennia. Quietly cycling through animals or isolated human populations.
In this stage the virus may not even cause serious illness. Scientists have come to the conclusion that changes in the carriers
biome such as an airstrip, new roads or even new buildings in which mice or rats can live and harbor the virus may cause a
rise in the infected population.
The Filoviridae family of viruses were unknown before the late 1960’s. Even today not much is known about it.
This is mainly a result of under funding due to the fact that many people don’t classify Ebola as a top health risk.
But what the researchers are worried about is the potential of a new strain of Ebola, and even with homeland security, the
unprepairedness of our country to an outbreak of Ebola with the right mutations and right circumstances may lead to unthinkable
consequences.
Due to the under funding there has not yet been a cure developed for any strain of Ebola. Patients receive supportive
therapy. This is basically balancing the patients fluids, electrolytes, maintaining their oxygen status and blood pressure
and treating them for any complicating infections. In fact there has recently been a study on a new vaccine in which a single
injection has been shown to protect monkeys from the deadly virus after only one month. Scientists are hoping that this vaccine
proves effective in humans. If so it may give them a chance to finally contain these dreaded outbreaks. The method they would
use is quickly organizing a ring of vaccination, this is the same method used in the past against non biological-warfare strains
of the smallpox disease. If in fact the
vaccination is correctly modified for human use, it may also be helpful in the fight against Marburg and Lassa Fearer
Viruses, and the SARS contra virus. The Ebola virus can spread easily from person to person if proper mutations occur (and
they have), so finding prevention for it is crucial in containing further outbreaks. If the results gathered from the research
on animals stay true with humans the Ebola virus may see a dramatic decrease in victims and outbreaks. Doctors and scientists
at the VRC have lately been studying and searching for the “prime-boost” vaccine. The “Prime-Boost”
vaccine strategy is basically an introduction of noninfectious genetic material from the normally infectious and disease causing
microbe to prepare the immune system and gets it ready to respond to a more lethal, infectious injection which is given a
few weeks later. They have come to find that after the second injection of an attenuated carrier virus containing key genes
is introduced to a host, the immune system response substantially “boosted” much higher.
Eight monkeys immunized by the boost process, were soon injected with an Ebola virus strain found in the body of a fatally
infected person from what was then Zaire, during the 1995 epidemic. The single boost vaccination had successfully protected
all eight monkeys from a direct injection of the Ebola-Zaire virus. Some monkeys were given higher doses than others, but
even the ones who had received the higher doses had not shown any symptoms after the incubation period and checked out to
not have contracted the virus. After the three week incubation period the monkeys did not show any signs of the Ebola virus
being present in their systems.
The symptoms of Ebola range from severe Hemorogic fever, which was found to be a symptom in the Zaire strain. Ebola Hemorogic
fever or Ebola HF is a often fatal, very severe disease in nonhuman and human primates alike. Incubation period for Ebola
HF can be from 2 to 21 days. First symptoms are abrupt headache, soar throat, joint and
muscle pains and weakness. These are than followed by diarrhea, vomiting and stomach pain. Later a rash, indicating major
internal bleeding appears, red eyes, hiccups, internal and external bleeding, bleeding out of eyes, ears, nose and mouth and
rectum. Other symptoms may include loss of appetite, blood failing to clot, Hepatic damage, terminal shock, lymphopemoa,
severe thromobocytopenia, transaminase elevation, and Hyperamylasemia. Also expect to have loss of memory, central nervous
system disorders and loss of hair.
Scientists and doctors are still baffled by the way the few people can recover from Ebola HF. High fatality rate, 80-90%
of infected die within a few days. This mainly is determined by the strain. The commonness of thee earlier symptoms make
it hard to detect Ebola HF early on, because if you have red eyes, a soar throat, and a headache, Ebola hemorrhagic fever
would not be your first guess. Although some strains appear to be asymptomatic. Doctors can also run Antigen-capture enzyme-linked
immunosorbent assay (ELISA) testing to determine if the virus is present in your body.
There is no real way to prevent the Ebola virus in humans to date, but safety precautions can be taken. First and foremost,
STAY OUT OF OUTBREAK AREAS, avoid areas of epidemics. If one has to enter an area of an epidemic, say for instance medical
and or government personal, the correct precautions should be taken EXTREMELY seriously. Absolute gown, glove, and mask precautions
are necessary around sick patients. These precautions will greatly decrease the risk of transmission.
This report was written for Health Class
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