A. HISTORY OF VIRUS
1. AFRICA, ZAIRE
B. SYMPTOMS AND AFFECTS
1. BLEEDING, HEMORRHAGING
2. DEATH W/IN 20 DAYS
1. NONE KNOWN
D. INTERNATIONAL EFFORTS
2. HISTORY OF VIRUS
A. WHERE IT STARTED
B. HOW IT IS SPREAD
1. NON AIRBORNE
2. BODILY CONTACT
C. WHERE IT EXISTS TODAY
3. SYMPTOMS AND EFFECTS
A. SEVERE FEVER, ABDOMINAL PAIN
1. INSIDES MELT
B. DEATH RATES AND TOTALS
2 SURVIVORS, BUT EBOLA VIRUS AS THE CAUSE WAS NOT
A. NONE KNOWN CURES, RESEARCH BEING PERFORMED ON
Ebola virus is a relatively recently discovered virus, that when it infects
humans, caries with it a 50-90% fatality rate. Symptoms of this deadly virus
include Sudden Fever, Weakness, Muscle Pain, Headache, Sore Throat, Vomiting,
Diarrhea, Rash. Internal results include Limited Kidney Function, Limited Liver
Function, and Internal and External Bleeding.
The incubation period for the Ebola virus ranges from 2 to 21 days, depending
upon the method of infection. A direct inoculation of the virus into the bloodstream of
a human will bring about symptoms markedly faster than other forms of less direct
contact. The virus is present in the male’s reproductive fluids, and can be transmitted
through sexual contact for up to 7 weeks after clinical recovery from the Ebola virus.
The Ebola virus can be diagnosed with laboratory testing of blood specimens
under maximum containment conditions – because of the high risk of infection to those
handling infected blood.
There is currently no treatment or vaccination available for the Ebola virus.
Transmission of the Ebola virus occurs by direct contact with the bodily fluids
of patients infected with the virus. The handling of chimpanzees that are either ill or
have died from the Ebola virus can also transmit the virus.
Any suspicion of infection with the Ebola virus should be treated with extreme
caution: immediate isolation from other patients and strict barrier nursing techniques
must be practiced. All instruments, clothing, or biological matter must be either
disposed of or thoroughly disinfected immediately.
The initial outbreaks of the Ebola virus occurred in 1976. Springing forth from
unknown origins, this virus held the nations of Zaire in fear as it quickly claimed the lives
of many of it’s citizens. As this was the first recorded outbreak of the Ebola virus, the
medical community was unsure of how to handle Ebola. The level of care in Zaire during
this outbreak was very low, and as a result of the many infected victims congregated in
public areas, the virus continued to spread among the denizens of Zaire. The intervening
years have slowly produced scientific data on the nature of the virus – yet treatment is still
unavailable for those infected.
The first outbreak, as stated earlier, occurred in Zaire in 1976. This first outbreak
was followed by one in western Sudan, also in 1976. In total, these two outbreaks have
been traced to the deaths of 340 people – resulting from the 550 plus cases that were
identified in these two nations.After lying dormant for several years the Ebola virus once
again made it’s presence known in 1979. Once again, no cause was identified as 34 cases
of Ebola were identified in Sudan. This occurrence brought the deaths of 22 patients –
showing a fatality rate of more than 60%, just as in the 1976 outbreaks.
The next instance of humans contracting the Ebola virus occurred in 1995. The
Ebola Zaire strain was discovered once again on April 10, 1995 when a patient
hospitalized for what was believed to be Malaria infected the surgical team during an
operation. Those involved with the operation developed symptoms indicating a viral
haemorrhagic fever disease. This outbreak occurred in the city of Kikwit, Zaire. Although
the virus was spreading at a rapid rate, a coordinated effort of international health services
was able to contain the outbreak. Present in this coalition of health organizations was the
Centers for Disease Control and Prevention (the CDC) and the World Health Organization
– aided by members of the medical community from France, Belgium, and several southern
African nations. In this most recent epidemic (defined as all cases occurring from 1 July
1995), approximately 233 deaths have been caused, and 293 cases identified as Ebola –
bringing the fatality rate to nearly 80% in the outbreak of 1995)
Ebola was also detected in the United States in 1989, but this strain of the virus, known as
Ebola Reston, is not harmful to the Homo Sapien population. In 1989 a shipment of
African Green and Rhesus Monkeys arrived in Reston, Virginia from the Philippines.
These monkeys were infected with the Ebola virus, yet no human cases were documented.
149 workers came into contact with these monkeys in Reston, Virginia and not one
became ill – although two did develop antibodies for Ebola Reston.
A recent outbreak of the Ebola Virus occurred in November of 1995. There had
been a rash of deaths in the population of chimpanzees living within the Tai Forest. On 24
November 1995, a Swiss researcher on the Cote d’Ivore of West Africa contracted the
disease from an infected chimpanzee in the Tai Forest. The researcher was rushed to a
Swiss hospital where she recovered. After an autopsy of the chimpanzee indicated that it
was showing effects similar to those visible in human patients, a search began for the
locale the virus is indigenous to. However, the Tai Forest comprises over 4200 square
kilometers, and field researchers were unable to locate the virus.
The Ebola virus has not been very researchable. Part of the difficulty is that the
virus is so communicable, research must be conducted in very strictly controlled
settings requiring safeguards and equipment that are beyond the reach of many
laboratories. Also, because of the Ebola virus’ very lethal tendencies, it is
extraordinarily difficult to obtain a specimen for research.
The most concentrated research efforts to date have been performed by the
World Health Organization and the Centers for Disease Control and Prevention.
Although some understanding of the virus has occurred, much of the information
needed to develop a treatment and vaccine still remains elusive to researchers.
Research has led to a better understanding of the pattern of symptoms which
the Ebola virus causes in humans. Most patients arrive overtly ill, dehydrated,
apathetic, and disoriented – further medical investigation quickly shows other
symptoms indicating an infection with the Ebola virus. The Ebola virus is best known
for the extraordinary amount of bleeding, both internal and external, that it causes in
it’s victims. The death of the patient usually occurs within 7 to 16 days, with the
specific cause being shock – often accompanied with severe blood loss.
As early as 10-14 days after infection with either the Marburg or Ebola viruses,
an immune response can be detected. The primary response of the immune system is to
produce antibodies against the surface glycoproteins. This response is relatively
ineffective in that the Ebola still flourishes within the human body and is fatal to most
infected persons. There is also little known about the cell-mediated response to these
The pathology of the Ebola virus produces lesions found in liver, spleen, and
kidney. They are characterized by focal hepatic necrosis and by follicular necrosis of
the lymph nodes and spleen. As the disease progress into it’s later stages, hemorrhage
occurs in the gastrointestinal track, pleural, pericardinal, and peritoneal spaces.
Abnormalities in the coagulation occur(blood), suggesting that disseminated
coagulation is a terminal event. Research also points out that macrophages and
fibroblasts appear to be the initial and also preferred site of replication by Ebola.
Experimental treatments have included human interferon, human convalescent
plasma and anticoagulation therapy. These treatments, however, have met with mixed
results and any success is quite controversial. The only effective preventative measure
currently known is to crate a physical barrier of some sort – surgical masks, quarantine
wards, et cetera – that is capable of blocking the transmission of the virus to currently
As stated previously, past research has been significantly slowed as a result of the
extreme pathogenicity of the Ebola virus, as well as the Marburg virus. Recombinant DNA
technology holds hope in that the molecular structure of the virus is beginning to be
understood. This type of research will also lead to an understanding of the way in which
this virus replicates itself and the interactions that occur between virus and host. The goal
is to gain an understanding of the frequency, ways in which it is transmitted, and also to
identify where in nature the Ebola virus naturally resides – to identify it’s initial host
Ebola timeline/ Overview
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