The
worst outbreak of Ebola virus in history happening now in West Africa
hasclaimed more than 700 lives, according to the latest count from the World
Health Organization. The deaths occurred in Sierra Leone, Liberia, Guinea and
Nigeria.
This outbreak is moving faster than our efforts to control it,
Margaret Chan, chief of the World Health Organization, said at a meeting,
asreported by Reuters. continue...
The Zaire strain of the Ebola virus thats involved in the
current outbreak has had a fatality rate in the past of up to 90 percent.
However, the fatality rate of the current outbreak is lower. Thats because 90
percent is when you receive absolutely no medical care,said Dr. Nahid Bhadelia,
M.D., the associate hospital epidemiologist at Boston Medical Center and
director of Infection Control at Boston Universitys National Emerging
Infectious Disease Laboratories.
Right now youre seeing with supportive care, theres a 60 percent
mortality in the field, she told HuffPost.
But how exactly does the virus work to provoke such extreme
symptoms Ebola is notorious for causing, in some cases, bleeding from the eyes
and ears and cause death? Bhadelia explained why the body has such a hard time
fighting off the deadly virus:
HOW DOES EBOLA ENTER THE BODY IN THE FIRST
PLACE?
Ebola is not known to infect people through the air you must
come into contact with the virus somehow in order to be at risk for infection,
Bhadelia said. Its transmitted through exposure to an animal that carries the
virus (such as a bat or primate), through exposure to the bodily fluids of a
human who is infected and symptomatic, and through exposure to items that have
been contaminated with the virus. People who are providing care for a household
member when theyre cleaning up vomit or diarrhea, they come into contact [with
the virus], and the way its transmitted is theres virus in the fluids, she
said. That virus gets into your own body through the nose, mouth and such.
Ebola can also survive outside the host for a significant period
of time as long as a couple of days at room temperature. Thats why infection
control is such a huge part of this, Bhadelia said. If you have sterilization
of equipment, if you have availability of disinfectant, things like IVs and if
youre able to clean all those environments and isolate patients effectively,
the outbreak would never take a foothold. This is why places with good
infection control and medical infrastructure face absolutely no risk for
outbreaks from this pathogen, she added.
WHAT HAPPENS IN THE BODY ONCE INFECTION
OCCURS?
Once the Ebola virus makes its way into the body, it gets in the
bodys cells and replicates itself. Then it comes bursting out of our cells and
produces this protein that wreaks havoc, Bhadelia explained. The protein is
called ebolavirus glycoprotein, and attaches to the cells on the inside of the
blood vessels. This increases permeability of the blood vessels leading to
blood leaking out of the vessels. The virus causes derangement in the bodys
ability to coagulate and thicken the blood, she said. Even people who dont show
hemorrhagic symptoms will experience this leaking of blood from the vessels
which can eventually lead to shock and, ultimately, death.
The Ebola virus is also a master of evading the bodys natural
defenses: It blocks the signaling to cells called neutrophils, which are white
blood cells that are in charge of raising the alarm for the immune system to
come and attack. In fact, Ebola will infect immune cells and travel in those
cells to other parts of the body including the liver, kidney, spleen and brain.
Each time one of the cells is infected with the Ebola virus and
bursts, spilling out its contents, the damage and presence of the virus
particles activates molecules called cytokines. In a healthy body, these
cytokines are responsible for provoking an inflammatory response so that the
body knows its being attacked. But in the case of an Ebola patient, its such an
overwhelming release [of cytokines], thats whats causing the flu-like symptoms
that are the first sign of Ebola, Bhadelia said.
WHAT DO THE SYMPTOMS LOOK LIKE?
Ebola generally starts with flu-like symptoms. Though its known
for the extreme hemorrhagic symptoms the bleeding out of the eyes, etc. not
everyone will experience these. In fact, only 20 percent of people will have
[these extreme symptoms] Bhadelia said. Some people may succumb to the illness
before it gets to that point, some may have minor bleeding, some may just have
bleeding of the gums, or bruising
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