It's time we talk about Ebola. It's been on the news a lot and for good
reason. It's one of the deadliest diseases humanity faces - the
second deadliest, technically.
and it's making a stand in West Africa. Plus, for the first time, two US citizens
with the disease have been flown home
for treatment. But don't bar the doors and windows, or get yourself walled up into
some kinda 2006 bird flu hysteria because we've met Ebola before
and we're learning more about it than ever.
[Sigla]
It used to be known as Ebola Hemorrhagic Fever
more recently Ebola Virus Disease. But what the media have lately been
referring to simply, and sometimes hysterically, as Ebola
is really one of at least five known species of the Ebola virus.
What they're referring to is the most dangerous
species known as Zaire Ebola Virus, or Zebov
named after the central African country, where it was first discovered in 1976
along the banks of the Ebola river. It's in the news because it has infected more
people this year than it has
any other year since that first outbreak. So far in 2014, it has infected 1,323 people
729 of whom have died. And the virus has moved into some of midwest Africa's major
population centers, including countries like Guinea
Liberia, Sierra Leone, and possibly the Nigerian capitol (biggest city) of Lagos.
So, it's newsworthy for sure and for plenty of reasons.
According to the World Health Organization, Zebov has an average
fatality rate of 83% .
But in some outbreaks, it has killed more than 90% of the people it had infected.
Ebola is a type of hemorrhagic fever. Which means one of its most prominent
symptoms is heavy bleeding
either internally or externally. But blood loss isn't what kills its hosts.
After causing flu-like symptoms, like vomiting and diarrhea, Zebov
targets the entire circulatory system, causing blood vessels to fail, blood
pressure to drop
and eventually all of the major organs to shut down.
But let's check our heads for a minute. For one thing, Ebola is definitely
contagious, but it's not as easily transmitted as, like
the flu. It's not an airborne disease. It's only contagious by infected people
who are exhibiting symptoms
at the time. And even then, it can only pass through close contact with bodily
fluids. That's why most of the people who are getting infected are health-care workers
working in pretty austere conditions
or family members of patients who treat their loved ones at home
and prepare their bodies for burial. But being on the same airplane or in the
same hospital as an Ebola patient doesn't mean you've
automatically been exposed to the virus. And in another little glimmer of hope, it
turns out that some people have developed a natural immunity to Ebola.
A study in 2010 found that more than 15% of people in the West African
country of Gabon carry
antibodies for the Zebov virus, even though there is no record of an Ebola outbreak
there.
Researchers think that those people were exposed to the virus over decades
probably through
fruit that had been contaminated by bats, which are the original carriers
of the disease.
But instead of getting sick, these people just developed natural defenses.
We are not sure why. But as you might imagine, there's a lot of scientific interest in
the people of Gabon right now. And of course
there's no vaccine for Ebola. But many prototypes are being developed.
You may remember news we shared last year about a breakthrough in this effort.
Biologists in Boston found that cells treated with a kind of compound called
Indoline Alkaloids
blocked the ability of the Ebola virus to replicate itself.
These alkaloids are the same class of chemicals that give many plants their
medicinal properties. Trouble is scientists haven't figured out why they work or how
to turn them into an effective Ebola treatment. But even beyond the short term
risks of the current outbreak, it's worth looking at the bigger picture.
The figures coming out of West Africa, while scary and tragic, pale in comparison to
other public health crises in the region. Last week, I mention that the incidence
of HIV in sub-saharan Africa is still over 12% in some countries
and more than 1.2 million people die from aids there
every year. Meanwhile, over 600,000 deaths occur every year due to malaria.
The more attention that all of these public health crises get
the better. So maybe the best outcome of this current scare might not be the
better treatment of Ebola. But also more money,
science and brain power being devoted to conquering even bigger threats
in West Africa and other parts of the world. Thanks for watching SciShow News.
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