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Current time:0:00Total duration:6:07

Video transcript

back in 2011 I'm going to write it down here our world's population was about six point nine billion that's a pretty large number and sometimes you know what I'm thinking about big numbers they all kind of melt into each other so I thought it would be helpful to just write it out so you could see it six point nine billion people and that's what I try to represent here with these little black circles that's my best attempt at showing all the people on the planet and you just have to take my word for it that it's roughly representative so what I wanted to point out is that the w-h-o the World Health Organization has said that about one in three people living on our planet so just divide this number by three one in three people has latent TB infection so this is an enormous number of people right I mean when you read that you might not think about it but that's actually 2.3 billion people with latent TB infection and remember when I say latent TB infection what I mean is that the bacteria is either dormant inside of someone's lungs or it's dead but it's really hard to tell the difference so we always kind of hedge on the side of being cautious and we treat them as if they have dormant bacteria in their lungs and sometimes you might even see the term LT bi so now keep your eye on the map and what I'm going to do is show you what that would actually look like so if I actually erased two-thirds of the people this is what you basically have left something like this and these people are the ones that we can imagine then have latent TB infection still a lot of people right so the w-h-o found that in 2011 there were also about 9 million individuals that had active disease this is actually people that are coughing and having you know chest pain may be having bloody sputum all sorts of signs and symptoms of active disease so that's a huge number of people and we know that a lot of those folks have active disease they're actually coming from this pool of latent TB infection now about 10 percent of these folks that have latent TB infection will actually go on to get active disease and you can break that down further and say well five percent will be in you know the first couple of years after they get the latent TB infection and another 5% will be over a lifetime will be in their lifetime so you can split it up so you can see that most of that risk that 10% risk is coming in the first couple years but in general if you think about 10 percent of that enormous number 2.3 billion that's a lot of sick folks right let me actually draw in here what 10 percent of these people would look like just so you get a visual idea maybe this person in Brazil would be sick maybe another person out here perhaps this person over here maybe someone in America and maybe someone in Mexico we've got five maybe a Canadian get six we got six people over there maybe seven eight a couple in India nine ten a couple of folks in China 11 12 13 14 15 I mean it's a lot of folks right 17 18 maybe a Nigerian maybe an Ethiopian something like this and let me just make sure I did the math right really quick a couple more let's just do one here and one there so this is 10% that's what 10% visually looks like so you get a sense for how many people are actually going to get sick and have active disease and we know that there are a couple of other groups of folks that are also going to get active disease some would be the folks that had primary infection right because you can get primary infection then immediately have what we call primary progressive disease or you might have secondary infection right you might have latent TB infection then you get another person coughing on you and we would call that secondary infection so these are the different ways that you might get to be part of that nine million who have active disease but I want to point out that this is a huge pool all right this is a large number of people and so many many many people are going to contribute to that nine million with active disease now you might be thinking wait a second the math doesn't add up you know because you have if you just a 10% of this enormous number that's actually way more than nine million people so how does that make sense but just remember this is a risk in a lifetime or in a couple of years and this is actually looking at how many people are sick with active disease in one given year and to extend a little bit further just want to make a little bit of space those folks are going to go on to actually some of them are going to go on to die so you're going to have in 2011 we had about 1.4 million people that died and ultimately that's really what we're trying to avoid right we're trying to avoid people dying of TB and we want to avoid people getting active disease because you know it's it's it's a horrible illness and so you can see why there's such pressure to try to find people that have latent TB infection and really intervene before they actually go on to get sick so the final thing I want to show you is actually another picture I think you'll find this interesting this is where this is actually 22 countries where 80% of the diseases so go on and take a look at this map we've got 22 countries in total right 22 countries and these account for 80% of the cases of TB so these together account for 80% so the majority of the disease in the world is coming from these places so TB cases so it's actually quite interesting right you can take a look at this and say ok so you can see that you've got some African countries you've got countries in Asia and you've got Russia and you've got Brazil out here and these countries combined make up the majority of where people are sick with TB