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