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Current time:0:00Total duration:14:22

Video transcript

let's take a step back and think about the entire planet the planet we live on Earth's we've got lots of little continents and water right I'm gonna draw that out here and if I was to ask you how much flu effects this planet all the people that inhabit this planet in one year probably the best place to go to answer that question would be the w-h-o and that's exactly what I did I went to the World Health Organization and I wanted to know how many people on our planet Earth in one year let me write that out here so we know that we're not talking about many many years just one year how many people are hospitalized from the flu so this is actually a pretty mind-numbing number look at this huge number five million three to five million end up going to hospital because they have severe complications of flu this could be anything from like pneumonia to bronchitis to you know having a horrible you know asthma attack something like that so this is not how many people get sick with the flu but how many actually end up in the hospital or have severe disease from influenza and then another number I wanted to look up is how many actually died of having the flu and you know a lot of people will say well you know the flu is not a big deal it doesn't really affect you much you just get kind of sick and if that were true then we wouldn't be having a quarter million to a half a million deaths each year from the flu this is a really kind of a sad commentary right when you consider the fact that this is something that we actually do have a vaccine for so in the world we have a huge number of deaths happening now whenever I hear statistics like this my mind always kind of takes comfort right I always think well I'm living in a developed country and I have you know health insurance and I can you know go to the doctor if I need to and so what are the numbers like in the US I mean I'm sure that they're obviously not as high as that and what I wanted to prove to you is actually the numbers are not insignificant right so in the u.s. we have the CDC and the Centers for Disease Control tells us that we have about 200,000 people going to the Hospital each year because of the flu now you have millions of people getting the flu right that's another number but this is just how many people end up going to the hospital because of it and then this is the probably the scariest thing we have 3,000 to 49,000 people dying of the flu every single year and this actually I wanted to see why they had such a big range so I actually looked at the at the study and it turns out between 1976 and 2007 they actually kept track of kind of how many people had died of the flu and this is not obviously an exact graph but I just want to show you that they said well one year the number was as high as 49,000 this is number of people that died because of the flu in the United States and one year the number was as low as 3,000 and I say as low as 3,000 but I mean 3,000 deaths is still a lot of deaths so we have thousands of people dying a flu and we have hundreds of thousands of people going to the hospital for flu so if someone ever tells you that it's not a serious problem in the US or and you know developed countries that is definitely not true and it's a huge problem internationally now I want to show you some interesting data this actually comes from the the CDC they actually put this on their website and you can check this out it's actually pretty pretty neat and helpful to understand exactly how we gather information about flu so the key word here is surveillance you know that you see this influenza surveillance report here as surveillance basically means how do we gather data around a disease or you know gather data around anything really so let's talk through that process the traditional way we do is we say okay we have a person let's say this person is me let's say I'm feeling pretty lousy from the flu right I've got a case of sore throat I've got some runny nose and maybe I've got some fevers and body aches so I'm gonna go to my doctor my doctor is gonna be over here in blue and my doctor is gonna be pretty smart pretty savvy and they're gonna figure out pretty quickly that I've got the flu right there smiling cuz they figured it out and so then they're gonna take that information they're gonna say okay well I have a person here by the name of Rishi and he has the flu and they're gonna send that information where it's gonna go to the hospital that they work in right or the clinic let's say so that clinic now has a record of all the people that kind of walk through and have the flu so now that clinic or that hospital is gonna also take that that list of people and you know it's protected confidential information so it may at this point not even have your name on it maybe they just have the total number of people with the flu and they're gonna send that over let's say to the county and I live in San Francisco so let's say this is San Francisco County so they send that information to my County San Francisco County and then that County is going to get that information they're gonna say well thank you hospital for sending it over and they're gonna take that whole list and they're gonna add it to all the other hospitals that sent them information and they're gonna get a bigger number and they're gonna get that bigger number and they're gonna send it to the state of California right the state of California gathers information about the flu and they're gonna say thank you so much County for sending it over this is California and California is gonna gather up all the information about you know who's got flu and their entire state all the different counties that send them information and they're gonna send that information finally to the United States kind of Public Health Authority and it's based over here in Atlanta so eventually the information goes to the Centers for Disease Control so this is kind of the chain of information right that we traditionally use and that's why over here it says you know this is estimates reported by the state and territorial epidemiologists rights all the different territories and states that are encompassed by the United States so that's what that means and this actually this graph is telling us that we're seeing regional and widespread flu in almost every state at the end of 2012 so just a couple weeks ago since today the data is January tenth now some really smart people got together and they said is this the only way to actually you know gather information about the flu maybe there's another way so some folks at Google got in touch with some folks at the CDC and they said let's let's put our brains together let's figure out if there are other ways that we can actually gather information now think about me know I had the flu right what else might I do well I might jump on my computer because I'm a I'm a computer kind of guy and I like to learn about what's going on and so I might jump on my computer and I'll say okay let me search in google right maybe I'll search in Google to find out what I might have so I'll type into Google and say hey Google tell me what I need to worry about and I'll go through and you know I might find that Google tells me that you know if you type in sore throat let's say I type in the word sore throat here it might give me some search results it'll say well maybe you should take this medicine or that medicine or am I type in the word cough right or fever these are all words that I might type in the day that I get sick and I might also go to the hospital or I might not maybe I'm not that sick so I think you know let me just type in these words and what Google gets is they get all the searches that Rishi did that day as well as all the searches that other people in my community are doing so maybe there are other people searching now maybe mr. red is searching and maybe mrs. blue is searching so maybe all these other people are searching as well for the same kind of words right and what are these words these are basically all flu searches right kind of searches related to the flu I'm gonna call them flu searches and there are many other terms as well but I'm not listing all of them just kind of some of them so you get a sense for what this means so Google what they could do is they could actually tally up the total number of searches related to the flu that are happening in a community let's say in San Francisco in one day and that total I'm calling this total right here flu searches that's the total searches for flu related terms in a day yeah at a San Francisco now over here we've got other searches right so let's say we've got searches for weather in Nepal maybe I'm going on a trip to Nepal or somebody in my community is going and they search for that or maybe someone is searching for basketball news they want to know you know which team and which team lost they want to know that and maybe a third person is searching for cellphones so really these are all the other kind of searches that are happening on Google right there probably thousands and thousands of them and you could tell you all these searches up and this would be the total searches in Google and this is again the search is happening in one day in one community this could be all the searches happening in San Francisco and maybe you know there's a person over here you know little girl in yellow and maybe this is a man in purple who's searching and maybe this is a person in green and these aren't necessarily different people right it could be maybe mr. red searched for sore throat and then later he was interested in basketball news so he actually was in both groups so really we're not killing people we're counting total searches that's the key idea here total searches is what matters in a day in some community now you could actually take these numbers and make some sense out of them this is where kind of the folks at Google and the folks at the CDC did something very clever and they said okay let's put this number here and this number here and let's divide by them so let's do flu searches flu searches divided by total searches total searches right and if you divide the two you're gonna get some fraction right some percentage and it's gonna be pretty small right because flu searches is is gonna be a small fraction of the total searches that are happening and then you could take that fraction this is where it gets really interesting and you could say okay let's look at a whole year right this fraction we got for a given day but you could do this every single day for a whole year and you can say January February March April if you go through the entire year the cantide calendar this is June let's say July this is August September October November December and if you did this 365 times you know each day you did this let's say or you could do this weekly however you want you would get some fraction some percent right and maybe the percentages would be small but you could graph them out if you wanted to and you'd probably notice something like this you notice that in the winter months the numbers get bigger and in the summer months the numbers get smaller right because in the summertime fewer people are probably searching for cough runny nose things like that because those things usually happen in the winter so you might get something like this this is percent over here so this is kind of a trend that you might see now as I said the people at the CDC and the people at Google were very clever to think of this and they actually compared data they said okay let's compare data from Google to CDC data let's see how they actually look side-by-side right here in my graph I had done one year right this is one year from here to here and you can actually see that this is basically the same thing this is from you know January through December so we're seeing peaks in the winter time and that's understandable but the great thing about this graph is you can see that Google Flu Trends actually line up really nice with the US data and the US data if you look down here comes from as we said the CDC so this is actually information from the CDC a lot influenza-like illness right and they're seeing or we're seeing that there's a fantastic correlation both in the timing right because the peaks are happening basically at the same time and also in the magnitude right so some years are smaller and some years are bigger right so it's actually pretty impressive that the data from searches that are happening on Google actually lines up really well with data the traditional way that we get data through surveillance in our public health system let me show you one more thing now so if you look currently so the last graph was six years I just want to quickly point that out this is six years of data 2004 2009 but if you look currently we actually have 2000 and where does the date here 2012 and 2013 and here we are between December and January in fact today's date is January January 10th January 10th and it's 2013 so here we are and you can see that the searches are really peaking out right this is looking at national data right you can also change it you could say well instead the US I'd like to look at Mexico what I'd like to look at Canada or you know some other country or you could say you know instead of looking nationally I want to look at some city or some state so you could change it in this it's actually something I encourage you to play with if you're interested go to google.org and play around check out your own country your own community and you can see how many people in your area are searching for flu related words and then finally if you actually look at the net or the international level you can actually see the map that's happening internationally globally and here are some interesting trends also appear right you can see all this activity in the northern hemisphere and a lot less in the southern hemisphere which makes sense because it's our winter season and flu is definitely a virus that affects us more in the winter time and you can see that you know some countries have really intense levels like the US and high levels like the Canada like Canada and some of these countries have more moderate levels or low levels like Europe and Russia in Japan