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Current time:0:00Total duration:12:47

Video transcript

so if you're watching this video I'm pretty sure that at some point in your life or in the lives of someone you know they've had the flu almost everybody is pretty familiar with how how awful it feels to get sick with the flu and when people talk about the flu they kind of talk about it in two different ways and we're gonna we're gonna get into both of those ways right now so sometimes they'll talk about the illness or the symptoms they had when they had the flu and other times they'll talk about the virus you know the actual virus that causes the flu so I'm gonna actually break it down the same way we're gonna talk first about the illness and then we're gonna get into the virus I'm gonna draw a nice little line down the middle so we don't get lost in this conversation so I can't help it but anytime I hear that someone has the flu I immediately get into this mode where I have a bunch of questions for them and I really just want to kind of convince myself that when they say I'd have the flu they really have the flu and they don't have something else so the questions that pop up my head the first one is usually is it abrupt or did it kind of start abruptly I'm gonna just write that was it abrupt and you know I might say do you remember feeling well one evening and then waking up sick or something like that do you remember exactly kind of when it started and most people with the flu can tell you within a day or two exactly when their illness started now another clue that something is the flu is that it usually lasts for about three to seven days so if someone is saying well I got sick with the flu and then four months later you know I started getting better that's a very weird story usually it would be a lot quicker than that so always think around three to seven days of course it could be a few few extra days than that especially when you're thinking about a symptom like the cough but generally speaking that's the time window then I really get into the symptoms themselves I want to find out exactly what made them feel so sick and there are two categories of symptoms the first is respiratory symptoms I want to know about respiratory symptoms and secondly I want to know about what I call constitutional symptoms constitutional symptoms and these this has nothing to do with the Constitution but it has to do with the body kind of thinking about symptoms that affect the entire body so let me make a little bit of space on the canvas and we'll first start out thinking about the respiratory side so respiratory symptoms let me draw out air coming into the body remember air has two major paths into your body it's gonna come in through your nose or it's gonna come in through your mouth right and when it comes in it's going to quickly join up remember air and the nose is gonna meet up with air in the mouth and it's gonna go down through the windpipe or the trachea we call it and it's gonna branch off into the right and left lung so this is my right lung over here and on the other side we've got the left lung and remember the left lung is also gonna be right next to the heart so we've got to keep a little space for the heart so these are the two lungs and this is the air coming in now someone says that they have a stuffy nose that's a really common one right they say they're congested or sometimes they might say a runny nose but any of these kinds of symptoms you can think in your mind of this picture and you can say well yep this is right along the path that air is gonna take on its way into the lungs so this is part of the respiratory tract now another symptom might be a sore throat a sore throat and here again you can see that the air is actually going to be passing right through the throat on its way down into the lungs and a really really common symptom you hear this all the time is cough and whenever people talk about cough I just usually think about the lungs being involved there so these symptoms stuffy nose sore throat cough you can you can think of this picture and really you can visualize they're going through and somehow these parts are being involved now exactly what's happening is that the virus is of course coming in right bring breezed in that's how it taken the flu virus and as it hits these different areas the cells are getting damaged and that's that's what we experience as a stuffy nose or sore throat or a cough it's really damaged cells that being affected by the virus now moving on to the other side the constitutional symptoms these are symptoms that I want you to think of as affecting the whole body so this is the whole body this is let's say these are the arms and the legs these are symptoms like fever now so much as they have fever it's very hard to point to one exact part of the body that's affected right you might say well I feel feverish really all over and if you're feeling feverish this face would be very sad like that so if you have symptoms like fevers and with fevers oftentimes you get chills as well I'm gonna put that together if you have fevers or chills that would be a constitutional symptom another one would be something like body aches you know if you are in bed because your whole body is aching you wouldn't point to any one place you'd say well it's just kind of all over and so that would be another constitutional symptom another another one that jumps to mind is fatigue kind of the same idea where your whole body is affected here so again when someone tells me about flu I'm thinking that they better have at least one of these respiratory symptoms and at least one of these constitutional symptoms so I think of them in two categories right and I want at least one from each category and they must have both if they're gonna get me convinced that they have the flu so scrolling up just a little bit just to make sure we don't forget it's got to be abrupt it's gonna happen over the course of three to seven days and they should have at least one rest or symptom and at least one constitutional symptom now this is good if I'm taking care of patients from you know thinking about a clinical setting like the hospital or the emergency room but what about if you're doing research well it turns out that the Centers for Disease Control and they do a lot of research around influenza and flu they have a definition that I want you to know about their definition and you'll see this is that the person has to have a sore throat or a cough one or the other I'll put a big order here and they have to have fevers so this is very similar to the definition I just gave you but this is the definition they use when doing research and when actually presenting data so it has to have these two things right sore throat or a cough and fevers and so this is the definition for influenza like illness influenza like illness and the short way of saying all this is ili influenza like illness so this again is the definition from the Centers for Disease Control so if you ever hear ili at least now you know what they're considering as being someone that has ili so this brings up kind of an interesting question and that's why I kind of started out by splitting things up between the illness and the virus I want to go over to the virus side and just keep in the back of mind this idea of ili now on the virus side let me just kind of sketch out very quickly in this green color what the influenza virus looks like I'm gonna label this influenza over here so this is my influenza virus and this little virus has got some RNA on the inside of it so it's got RNA in here and I'm gonna draw out the RNA just so you can see it I'm gonna use two different colors so let's use like a purple color here and one important thing about this RNA is that it's broken up into little pieces the way I'm drawing it here so it's got some purple chunks and let's draw some yellow chunks of RNA as well and this RNA of course is as I said genetic material so it's going to be coding for proteins so you've got some proteins and let's say that you've got some proteins out here on the surface and you know you could imagine that those yellow proteins come from one of those yellow RNA segments and you've also got some purple proteins over here some purple proteins I'm going to draw out some purple proteins here for you so let's say that the purple protein we can call that H and the yellow protein we can call that n so what you're getting here is that you're seeing a couple the important parts of influenza virus and I just wanted you to start getting familiar with the fact that it has you know RNA on the inside that it's broken up into chunks that it's got some surface proteins on the outside and a couple of those important ones we call them h and n for short and I'll tell you more about them in a future video so this is influenza virus and now the question is if you have someone let's say I've got a friend or a family member who tells me that they had an abrupt illness that was six days and they had fevers and a cough well it sounds like based on what I said that this meets of course the CDC definition for influenza like illness and so if I tested them let's say actually you know checked their nose with a little nose swab and did a test you would expect that I would actually find influenza in there and most of the time I would actually find influenza there but not always and this is actually an important concept that there are actually believe it or not some of these little copycat viruses I'm gonna draw a couple copycat viruses here for you I'm gonna write out two of them there are actually more than two but we're just gonna talk about two of them and I'm not gonna draw them accurately this is just kind of a visual representation just to kind of show you what what they are and write up their names one is called Rhino virus Rhino virus and you may be aware that Rhino means nose and actually Rhino virus loves to infect the nose and that's actually why it's called Rhino virus and another copycat virus I'm gonna draw it looking a little different maybe a sideways looking thing something like this this guy this is RSV RSV and the full name of RSV is respiratory so you know it affects the lungs sinks Ischl virus respiratory syncytial virus and we'll talk about that another time as well but the idea here guys is that these copycat viruses and this is interesting they can actually sometimes fool us into thinking that we're dealing with influenza because some of the symptoms you get with Rhino virus and that you with RSV end up being pretty similar to the symptoms you get with the flu and so as a result we have to have some way of telling them apart and that's why actually you may have heard of the term the cold let me actually bring this down and actually show you now the cold and the flu side-by-side and how to kind of distinguish between the two so when you have let's say the flu we said that usually you would have some respiratory symptoms check and you'd have some constitutional symptoms check but if you have the cold kind of the common cold we call it then you generally only have respiratory symptoms you don't typically have fevers and chills and body aches and fatigue you don't usually have that stuff with the cold so that's kind of the easy and quick way to distinguish between the flu and the cold and those are the questions I always ask you know patients of mine I say well did you have body aches or fatigue and if the answers to all those kinds of questions are no I'm thinking AHA this person has the cold but of course this is an exact right this isn't perfect and that once in a while people will actually fool you and they will actually have one of these copycat viruses the Rhino virus or RSV or adenovirus there are many other ones and they'll actually have influenza like illness they'll actually have sore throat and fevers and body aches and so this is important to know that every single time we clinically think someone that has you know flu illness doesn't necessarily mean that they have the influenza virus