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Current time:0:00Total duration:9:47

Video transcript

so let's say you're walking down the street and you see this person this green sickly person and this person is coughing and sneezing and you know you feel really bad for them right because they they look awful they just must feel awful as well and the thought that goes through your mind is how do you avoid getting sick as well because of course you don't want to feel this way either right and so you want to think about all the things that you can do to make sure you don't get sick from this person and so what are some of those things that you might be able to do to try to avoid getting sick well let's think through it how are you interacting with your environment what's the only real way in which you interact well it's when you touch things right you usually have your feet and your body covered up but your hands are always exposed and they're always kind of touching things and then you usually kind of turn around and touch your mouth your eyes your face so two real quick things that you can do to try to prevent getting sick are simply making sure that you wash your hands and that's why I always hear that message you know wash your hands after going to the bathroom and before you eat and that's the reason why and the other key messages don't touch your face right you want to make sure you avoid your mouth your eyes your nose because that's where the the viruses get into your body so don't touch your face so these are two really good ideas right but what are some others what else can you do well you can try and this isn't always possible you can try to avoid the person altogether you could try to just kind of move away right you could say well let's make some distance over here so you're further away from this person and that's another possible strategy and you know like I said it doesn't always work but when you can avoid someone that's always a good idea so avoid sick people and finally and this one is gonna be the the main point of this video is you can actually get vaccinated you can get a vaccine that will actually prevent you from getting ill so flu vaccine is something that a lot of people you know have strong feelings about and the first thing I want to point out is on this list of prevention it's probably the most important it's probably the most effective way of preventing that you know getting sick from the flu so certainly think about it but if you're gonna think about it and you want to think critically about doing something like this you want to make sure it's a good idea right I do we really have any evidence that it really does help or or is it the opposite does the flu vaccine actually make you more sick does it give you the flu so let's talk about that let's think through how the vaccine works and what we know about it so there's some research that's been done on flu vaccine I'm gonna present you with what we've learned so far so a group out of University of Michigan actually came along and they said well let's let's figure out the answer to whether vaccine is a good idea and let's actually take you know let's start over here on the left side let's take an injection and fill it with saltwater so this is regular old saltwater or something very similar to it and it has no real effect at all in fact sometimes people call this placebo a lot you write that over here placebo so that's one side and on the other side let's actually come up with a vaccine and this vaccine I'm gonna draw out it looks basically the same it's actually also an injection and this injection is full of dead virus so they literally take live virus when real live virus has kind of an envelope and it has RNA on the inside I'm going to kind of sketch that out and what they do is they actually have different ways of killing it they literally just destroy this thing and just like human beings you know if you're killed you cannot come back to life and a virus is the same way once a virus is dead it is dead forever and so this dead virus is lying here on its side completely and utterly dead right and this dead virus then they take it and they put it into the vaccine so this is what is in the vaccine this is our flu vaccine let me label it over here flu vaccine so two groups of people then are going to get two different types of injections and they actually had hundreds and hundreds of people involved in this study but I'm just going to show you kind of a representative slice so let's say the is a hundred people over here and that's a grid so each square represents one person and there's a hundred people over here and these people they don't know which vaccine they're going to get they don't know if they're going to get the salt water or the flu vaccine they're what we call blinded in this study and I should also tell you that these people are very healthy and they're young adults so they're between 18 and 49 years old they're healthy and the two groups are fairly similar in terms of you know the amount of or the number of men and women in each group and their age breakdowns and the two sides are fairly similar so these two groups get the salt water of the flu and they don't know which is which and they're told over the course of six months over the over the course of the flu season to keep track of illnesses and if they get flu I'm gonna sketch them out in red what they actually did is they said hey if you get the flu let us know and we'll confirm it well actually do a lab test to make sure that it really is the flu and that it's not just you know some other illness that you think you have so they actually took all these people that said they had the flu and I'm only gonna draw him in red if they were confirmed by PCR that was the lab technique they used so these are called PCR confirmed so that's lab laboratory confirmed illness with flu so these are people with PCR confirmed illness and they were you can count them out out of a hundred people in the first group in the salt water group we had a total of ten individuals so about ten percent of these folks were ill with the flu over the flu season and on the flu vaccine side we also had some people sick with the flu so that's actually the first thing you should know is that the flu vaccine does not prevent you 100% from getting the flu but look at how many people I shaded in in the placebo side I said there were ten out of a hundred people I got sick and on the flu vaccine side only about three out of a hundred people got sick and both actually I should put arrows on both sides both were PCR confirmed so what does this mean you know how do you take this and kind of make some sense out of it well there's a term called vaccine efficacy vaccine efficacy and what it kind of refers to is how good is the vaccine at preventing you from getting sick so this is the term vaccine efficacy and sometimes you might even see the term ve sometimes people use ve for vaccine efficacy and the way you calculate it you say ve equals the proportion of people that got sick with the salt water that was ten out of a hundred minus the proportion that got sick with the flu vaccine so minus three out of a hundred and you divide by the group that did not get vaccine and so you can take this and you could simplify it you could say well this is basically seven over a hundred divided by ten over a hundred and you can make it even simpler by cancelling the hundreds out and you say well this is just 7/10 and to make a percent out of it you multiply seven tenths by a hundred percent so if I was to describe the ve or the vaccine efficacy based on this study I would say well flu has a 70 percent vaccine efficacy so you see how we get that number it's fairly simple right just comparing the two groups to each other and there have been many studies on flu and the CDC actually kind of took all this data and they said well in general the ve or the vaccine efficacy for the flu vaccine is is usually between 60 and 70 percent that's kind of the number that they usually quote for this vaccine so let's now take that number 60 to 70 percent ve I'm gonna write that down here so we don't keep trying or don't lose track of what that is and let's take that back up here to our little example right we said that you know there are a few ways to try to prevent the flu and if I imagine now that there's a force field around me let's say there's a little purple force field around me and this force field protects me from germs I'm gonna show germs kind of coming in and bouncing off my force fields well this would be really accurate if I was describing a hundred percent vaccine efficacy me if I get the vaccine I'm completely unable to get sick but we know that's not true we know that it's actually closer to 60 to 70 percent so for 60 to 70 percent let me show you what you can kind of change this picture to look like instead of making it completely impenetrable you can just draw a few holes in it so a few holes there may be a hole there and maybe a hole down here so now you can show a few of the germs kind of breaking through and getting in right maybe getting it over here but many of them actually still kind of bounce off and so you're still protected by a lot of the germs but some of them can still get you sick so probably the best way to avoid getting sick then is to get your vaccine but still make sure you wash your hands don't touch your face and avoid sick people