Ebola Virus

In the world today, there are many known deadly viruses, but few present as
great a threat as Ebola, the virus that causes Ebola Hemorrhagic Fever. Key
factors in understanding Ebola HF include: Its history, plan of attack, and the
diagnosis and treatment of the disease. The Ebola virus can, and usually does
cause a disease called Ebola hemorrhagic fever, which is a Viral hemorrhagic
fever. According to the proceedings of the 4th National Symposium on Biosafety,
the clinical definition for Viral hemorrhagic fever is as follows. "Viral
hemorrhagic fever is an acute infection that begins with fever, myalgia, malaise
and progresses to prostration. It shows evidence of vascular dysregulation and
increased vascular permeability and can include multisystem involvement. The
hemorrhage indicates extent of small vessel involvement but not necessarily
large in volume. Shock, encephalopathy, extensive hemorrhage, and poor prognosis
should be expected" (4th National 2). The Ebola virus is named after a
river in the Democratic Republic of the Congo (formerly Zaire) in Africa, where
it was first recognized. The Ebola virus is closely related to the Marburg
virus. Both are members of a relatively new family of viruses called Filoviradae.

Ebola hemorrhagic fever is classified as a BSL-4 (biosafety level 4) agent,
which is the most dangerous in the Centers for Disease Control and Prevention (CDC)
classification system. BSL-4 agents are exotic agents that pose a high risk of
life-threatening disease, and for which there is no vaccine or therapy.
"Ebola hemorrhagic fever is a severe, often-fatal disease in humans and non
human primates (monkeys and chimpanzees) that has appeared sporadically since
its initial recognition in 1976" (CDC 1). Common human perceptions of this
virus are, for the most part, accurate in that it is a highly contagious agent
that can cause a fatal disease called Ebola hemorrhagic fever. Although, there
are a few misconceptions such as the belief that the virus can be transmitted
from person to person through the air, which is not known to be true, and later
explained. Also, contrary to popular assumptions, humans are not carriers of the
virus, as we are with the influenza virus, 2 for example. The initial patient in
an outbreak must have somehow contracted the virus from an infected primate
carrier, such as a monkey, which will also be explained. Listed, are some of the
more pertinent outbreaks of Ebola hemorrhagic fever. In 1976, the first and
largest outbreak of the virus occurred in Yambuku, Zaire, killing 88% of 318
infected patients. This species was named respectively, Ebola-Zaire, and has
appeared in four other outbreaks to date. The Ebola-Sudan species appeared,
naturally in the cities of Nzara and Maridi, Sudan also in 1976. The death toll
was much less than the Zaire outbreak at 53% of 284 infected persons. In 1995,
the Ebola-Zaire species struck again, killing 81% of 315 reported cases. This
time, the outbreak occurred in Kikwit, Democratic Republic of the Congo, which
was the new name Zaire. In the United States, to date, no case of the disease in
humans has ever been reported, not to say the virus has never been here. In

1989, 1990, and 1996, Ebola, or at least a weaker species of the virus was
brought into quarantined facilities in Virginia, Texas, and Pennsylvania by
infected monkeys imported from the Philippines. In both 1989 and 1990, four
humans were infected with the virus, but did not become ill. Obviously, the
species of the virus, now called Ebola-Reston, that entered the United States
was a much weaker species than those in Zaire and Sudan. "The Reston
outbreak served as an important wake-up call for the U.S. Army and CDC research
groups. Among other things, it demonstrated the need for better diagnostic
tools" (4th National 10). Transmission of the Ebola virus is highly
dependent upon the initial infection of a human. It is hypothesized that the
first infected human in an outbreak must have been infected by an animal. This
first infected patient in an outbreak is called the index case. At this point,
humans can transmit the virus from person to person in several ways. People can
contract the Ebola virus through contact with the blood and/or secretions of an
infected person. For this reason, this virus is commonly spread among family
members in the course of feeding, holding, or otherwise caring for infected
persons in any way that they would come in contact with such 3 secretions. Also,
people can be exposed to the virus through contact with objects, such as
needles, that have been contaminated with infected secretions. The