The Ebola virus is uniquely terrible
for many reasons, but it doesn't actually kill you. Your own immune system
does.
In its struggle to beat back the
virus, your immune system's reaction ravages the rest of your body, leaving
your blood vessels weak and leaky.
Soon, blood and plasma start pushing
through, sometimes coming out of your pores and every orifice.
But long before the body begins to
fail — around the time Ebola first enters the blood — the virus starts tripping
up our defenses.
Here's how it kills, how it spreads,
and how it can be treated. In every step of the way, this deadly virus is
uniquely terrible.
How It Gets In
Ebola is a filovirus, a type of virus made from a tiny string of proteins that coat a single strand of genetic material. Particles of the virus live in an infected person's blood, saliva, mucous, sweat, and vomit.
Ebola is a filovirus, a type of virus made from a tiny string of proteins that coat a single strand of genetic material. Particles of the virus live in an infected person's blood, saliva, mucous, sweat, and vomit.
When someone is at the height of the
illness (typically after five or more days), one-fifth of a teaspoon of that
person's blood can carry 10 billion viral Ebola particles, The New York Times reports.
An untreated HIV patient, by
comparison, has just 50,000 to 100,000 particles in the same amount of blood;
someone with untreated hepatitis C has between 5 million and 20 million.
If those particles find an entry
point, like a cut or scrape, or if a person touches his or her nose, mouth, or
eyes with fluids that contain them, they get to work quickly.
How It Kills
Once inside the bloodstream, the virus targets a compound called interferon. Interferon, named for its role in "interfering" with the virus' survival process, alerts the rest of the immune system to the presence of a foreign invader. Normally, interferon would deliver its warning message straight to the cell's command center via a special "emergency access lane."
Ebola is too smart for that old
trick.
The virus hijacks the delivery
process — preventing the immune system from organizing a coordinated attack —
by attaching a bulky protein to the messenger. In its misshapen form, the messenger
can't enter the cell. The immune system remains unaware of the problem, and the
virus gets free range to attack and destroy the rest of the body.
This is when Ebola goes on a
replication rampage. Once the virus starts growing, few things can stop it.
The virus starts infecting organs, killing the cells inside and causing them to burst. All of their viral content pours into the blood. By this
time, the immune system begins responding to the crisis in turbo mode, but it's
far too late. Rather than destroying the virus, our defenses simply rip our own
bodies to shreds — from the inside out.
The World Health Organization has
said the virus seems to kill about 70% of people infected, though it's hard to know the true numbers while the
outbreak is still in progress.
How It Spreads
Although Ebola spreads less easily than a cold, because it isn't airborne, the Ebola virus is far more persistent.
Although Ebola spreads less easily than a cold, because it isn't airborne, the Ebola virus is far more persistent.
Like cold germs, Ebola virus
particles survive on dry surfaces, like doorknobs and countertops, for several hours. But
unlike a cold virus, which primarily infects the respiratory tract, Ebola can
also live in bodily fluids like blood and saliva for several days at room
temperature.
Doctors have found Ebola in the
semen of men who have survived the virus up to three months after they recover.
It's important to remember that
someone with Ebola isn't contagious until he or she starts showing symptoms.
This happens when enough of a person's cells have been overtaken by the virus,
a process that scientists say appears to require a hefty load of viral
particles in the body.
There's also the prospect of Ebola
mutating into something more deadly. Peter Jahrling, one of the head scientists
at the National Institute of Allergy and Infectious Diseases, thinks the virus
could already be changing into something more dangerous, Vox reports.
In recent tests with Ebola patients
in Liberia, Jahrling has noticed that the infected seem to have more of the
virus in their blood, which could presumably make them more contagious.
And even worse, it preys on our
human need to touch and care for the sick, which is why much of its spread is
to caregivers and healthcare workers.
"The mechanism Ebola exploits
is far more insidious," as Benjamin Hale wrote in Slate. "This virus preys on care and love, piggybacking on
the deepest, most distinctively human virtues."
That's why the virus strikes
children, their parents, families, and communities. All it takes is one small
slipup, one uncalculated act of humanity, and the disease spreads even further.
How It Is Treated
It's tough to believe that anyone could survive Ebola, given its quick and violent progression. But two Americans did, and thousands of people in Guinea, Liberia, and Sierra Leone have as well.
It's tough to believe that anyone could survive Ebola, given its quick and violent progression. But two Americans did, and thousands of people in Guinea, Liberia, and Sierra Leone have as well.
The virus' quick progression makes
comprehensive treatment in a well-equipped facility key for raising one's
chances of survival. If doctors can keep a person strong enough for long
enough, that person's immune system can eventually clear the virus on its own.
In Atlanta, two Americans were nursed back to health with a combination of experimental drugs and traditional
treatment. By keeping their patients' organs working with intravenous fluids
(to replenish the body with the fluids it is quickly losing), ventilators (to
keep the lungs pumping oxygen throughout the body), and drugs to keep blood
pressure from dipping dangerously low, they gave them the best chance of
survival.
That sort of treatment is pricey,
though.
The bill for the average Ebola
patient treated in the US is a lofty $1,000 per hour. In West Africa, where that sort of money isn't available,
most patients simply go home to die.
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