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Current time:0:00Total duration:11:15

Video transcript

so Ebola virus disease has been in the news and today is September 16th and I just want to mark that on the calendar so we can keep track of kind of where things are as they stand today and these Western African countries are kind of where we're seeing the disease Nigeria and Liberia Sierra Leone Guinea and also Senegal all combined have more than 4,000 folks that have been sick with Ebola and actually over 2,000 people have died of Ebola and I just want to contrast that with kind of geographically kind of where we've seen past outbreaks that are big and when I say big none of the past outbreaks have even compared with the size of the current outbreak but also the geography is different you see in the past it's been more central Africa and so those are kind of two interesting points about the current outbreak and and while we're talking about Central Africa I thought it would be kind of worth noting where the name of Ebola comes from actually there's a river down here in Central Africa back in 1976 there was the first outbreak that we tracked and it was actually named after the Ebola River because that's the region where this was first noticed so this current outbreak to understand it in its magnitude I think it's useful to kind of take a little bit of a larger view and understand how it transmits or how it spreads in the natural environment and usually these guys that I'm kind of shading in green these guys are are thought to be kind of one of the the animals out there that may be kind of spreading the disease around so fruit bats are one of the culprits that people suspect and they also actually get sick with Ebola and so this one I kind of sketched in green and when they get sick they can spread it to other bats in their bat community and this becomes then that the community becomes a natural reservoir we call this natural reservoir of disease or a virus and this is where it kind of circulates normally and so we wouldn't even think about Ebola if it was only affecting bats probably wouldn't worry about too much but what happens is that every once in a while it affects a human in the way that this might happen is let's say this person goes in their front yard and they notice a dead a door a sick bat and they try to care for it and they might get some blood or stool from that bat on their their hand and it can kind of go into a wound maybe they have a cut or I can go kind of in their mouth or if they rub their eyes or nose so all of a sudden the virus now has a way into the person and so that's kind of how we think that first person might get sick in that first person we actually have a special name especially if there's an outbreak and that name is an index case we say that this person is the very first person who got sick with the disease here Ebola and now looking at our calendar if this person got sick on the 16th today then their first symptoms are not going to be today they're going to happen in a couple of days all the way through three weeks so really kind of a long a window in terms of when their first symptoms might happen it could be this month might even be all the way through next month because the 7th of October would be three weeks and generally we notice that symptoms happen kind of in this window I'm going to draw right here so seven to ten days that's when their very first symptoms start to appear so they're not immediate and the first symptoms are kind of vague they're there things like you know they might feel a little feverish or they might get like a little headache maybe some muscle aches but kind of just general symptoms not feeling very well and at this point people think well you know maybe it could be anything some flu or something so they don't usually go and try to get medical help but then what happens is that the virus kind of spreads through the immune system and starts getting into all sorts of different tissues and it can cause problems in their stomach they might want to vomit or have diarrhea you can go to their lungs I'm shading in their lungs they can might you know start coughing it can cause rashes I can cause you know muscle aches it can cause redness of the eyes conjunctivitis we call that it can also cause inflammation around the brain itself meningitis or it can cause bleeding of the nose or the mouth the gums and in fact that bleeding is really classic because we think of the virus traveling in the blood and so bleeding is a really important thing to notice because it's very very transmissible you know people can get it from the blood and the word for virus and the blood is kind of viremic virus virus in this case it's the Ebola virus and emic means in the blood so when the virus is in the blood we would say there viremic and at this point they might say well you know I want to go and get the help of a doctor and so if they go to get medical help the kinds of things that they usually would get would be like IV fluids if they're dehydrated if they're having difficulty let's say breathing they might get some oxygen if their blood pressure is low they might get some medications to help their blood pressure kind of come back up to normal so these are the kind of things that people do and you know in western Africa they have all this support out there you know they have medical tents set up to kind of help people that have Ebola and so all the care they're giving is considered supportive care and there's no real specific anti Ebola medication again we're here on September 16th and people are researching it but at the moment there is really just supportive care to help people that are sick and nothing specific that targets the virus now they're worrisome thing this is now just I want you to just kind of wrap your head around this is that with supportive care what we're seeing in this outbreak on average is a 50% or so fatality rate meaning for two people with Ebola one will die it means it's a flip of a coin which is frightening I mean if you come down with these symptoms and you're waiting to find out if you have Ebola or not or if you've just found out that's a really really scary proposition that half of the people with this diagnosis are gonna die and that's exactly the reason why the world is kind of watching and an intervening and helping to make sure that we get this under control so in addition to the supportive care the other big area that we kind of think about is how do you avoid transmitting the virus from one person to another so let me just sketch in a second person here so here I've drawn a second person and the question becomes how does Ebola get from the first person to the second person how exactly does it move and the quick answer is that it moves through bodily fluids so bodily fluids include everything from blood to vomit and die riah or stool and these are kind of the big ones especially blood very very infectious but also stool and vomit because a lot of these patients are sick and in bodily fluids could also be things like saliva and sweat but again these first few that I've kind of written out are the ones to really keep in mind and blood in fact is it's an interesting one there was a study that I think is pretty cool and kind of illustrates the point where they showed that one drop just one drop of blood from a monkey that had Ebola was enough to carry with it a million little Ebola virus particles and that was thought to be enough to infect a million monkeys so kind of the idea that one single drop could be enough to really decimate a population so it kind of drives home the point that if there's a drop of blood just a single drop or another bodily fluid that really gets over let's say over into this person's hand and they can kind of go from there to if they touch their face it can get entry into their body through their nose or eyes or mouth or let's say they have a little cut it can actually make its way into the blood through that cut so a few kind of interesting ways that that that bodily fluid can travel but really then it gets a ticket into the second person and the second person can get sick and of course that could happen with stool or vomit as well now another question I think a lot of people ask is what about airborne you know can use can you breathe this stuff in and that's a big question the idea I think is literally is it kind of floating in the air and the answer is no you know it's not really like other viruses like measles and some other ones where it's airborne so let me just cross that out so it's very clear it is not airborne in fact I think a lot of the confusion comes when you think about things like sneezes so with the sneeze you can imagine like kind of you know you've we've all seen those those sneezes or had those sneezes were kind of a big droplet of goo or mucus kind of goes out and you get this kind of shower right of droplets and these kind of right around where you're standing just right in your immediate vicinity and that's not going to affect anyone that's kind of standing away from you and you could imagine maybe in kind of a strange scenario let's say there's a person kind of hanging out right here right next to somebody's shoulder and they're just kind of sitting there they might get hit in the face with one of these droplets and and maybe then you could say well you know they're there for they got hit and they they're sick with Ebola but again it's the droplet which is a bodily fluid and not the fact that they were just breathing you know air like like it someone that was standing away so that's not a typical scenario and that's why we don't call this airborne one quick thing I should mention is that you can get virus that kind of hits a surface and if it hits a surface like a table or the floor it can actually survive on that surface they think for days two weeks and so it is an important point because then that means that if someone's been in a room you really have to decontaminate that area and get rid of all those little dried up droplets that are sitting on the surface to make sure that that room is actually really quite clean again so what it boils down to is that the real way to kind of prevent the spread of this disease is to make sure that these folks are isolated if they are sick with the illness and over here all the caretakers they should be wearing protective clothing they should be wearing gloves you know to make sure that they don't get blood on their hands they should be wearing gowns to cover up the rest of their body so they don't expose any kind of wounds their cuts or anything like that they should be also protecting their mouths with a mask and goggles as well and so this is actually exactly in the nose so all this should be kind of covered up and so even working in these conditions can be really tough I mean these full body suits can get very very hot and it can be very very difficult to work in these conditions but this is really what you want to see to isolate Ebola from one person not getting to another and and in addition to just hospital workers of course you also have to remember the fact that it's going to be you know funeral directors that are working with dead bodies which can actually again spread virus believe it or not a dead body can actually spread for weeks after the person has died it can be lab workers that are dealing with specimens or family members actually are huge so all these different people are risk and by doing this you basically prevent the virus from spreading and hopefully end this scourge that's happened in western Africa