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Video transcript

so every winter a lot of kids come in and see me because they've got the flu and I've got to make a decision for each one of them I've got to decide am I going to get the flu test in this particular child right so when I see a kid that's sick here's what I'm thinking I'm thinking well the first thing I've got to decide is do I really suspect the flu and this is when I ask a lot of questions of you know the the person who's sick or the parents I say well when did it start was it abrupt because that's my first clue that it really is the flu the second clue is how long did it last and they might say well you know we're in the middle of it it's been a few days but if they tell me it's been weeks and weeks or months and months then of course I'm thinking it's something else right it's not the flu then and finally if they tell me that you know they're having respiratory symptoms then that's of course really important that sounds like the flu but they also have to have some constitutional symptoms right they must have some sort of fever fatigue to kind of convince me that this sounds like the flu so let's say that the person has these symptoms they have me suspecting that they have the flu is that enough for me to get a test well not really I've also got to think to myself is they going to change my plan so if the flu test results are going to change my plan then I'm much much more likely to get it right but let's say that someone comes in with a fever and they're having a cold symptoms like runny nose congestion and it turns out to be the flu and I tell them well you know you look pretty well why don't you go home and get fluids and rest and you'll feel better in a week well in that same scenario if the flu test was negative then I would say well maybe they have one of those other viruses one of those copycat viruses like Rhino virus or RSV or something else and I would say well why don't you go home and get plenty of rest and drink plenty of fluids and you'll feel better in a week so you notice I'm saying the same thing my plan is basically the same and so in that scenario it doesn't really make a lot of sense to me to get a flu test because it's not going to change my plan my plan is basically rest and fluids but sometimes every once in a while the flu test actually does change my plan and let me tell you what those circumstances would be so let's say for example I've got a patient and they're in the hospital and they're sick and we don't know what they're sick from you know they're having fevers and they have you know a bad pneumonia we don't know what's going on and I get a flu test and it's positive then that's really helpful in guiding my my thought process right then I might not even need other testing I don't have to look for other bugs so it might get rid of the need for further testing and it might help guide what I do next and so is in some patients where you're you're confused about what's going on it really is quite helpful to have a positive flu test another instance would be if I have a patient and I want to treat them with a medication you know knowing if it's flu a or flu B might affect my medication choice right so it could affect the medication that I choose to offer them I want to be very clear if I have a patient that's sick I'm not going to wait to find out you know whether the flu results were positive or negative I'm going to probably start treating them for the flu if I really suspect it so I wouldn't wait on the results of a flu test to treat but it might help me change my medication choice later or it might help me figure out how long I want to treat for there are lots of issues that you can resolve by getting a flu test in that situation and finally what about other choices that have to make you know things like where do I place a child in the hospital and I want to make sure if he doesn't have flu I don't put him with kids that do because then he could get another illness and so it could affect Hospital infection control choices so I'll write that as a third option infection control there are many other instances too you know you could think of outbreak situations where you really want to know how many people are sick or or what they're sick with exactly where you might want to get a flu test so many many places where a flu test is useful but not always many times I also don't get a flu test let me draw up a little bit of canvas maybe I'll just leave this up for the time being let me draw a little face here for you so this is a person with their head tilted back this is their eye and a lot of times what you'll do is you'll do what's called a rapid test that's one of the most common test that's done and the rapid test you can kind of get a sample by sticking a nasal swab almost like a giant q-tip kind of at the back of the throat and you go through the nose the key with the nasal swab is you want to make sure you go back far enough so you get cells not mucus you want to make sure you get cells because that's where a lot of the virus is really hanging out and you don't want to get just mucus because you may not actually find the virus that way and another way to do this rapid test instead of the swab approach is you'll see sometimes people actually wash they'll squeeze a little bit of saltwater back there and then they'll suction it back out so they'll actually going to squeeze some saltwater suction it back out it's usually a deep suction because again you want to make sure you get those cells you don't to get mucus and they'll send that off to the lab so this rapid test this rapid test that's what it's called is as I said before it's one of the most common tests that's done it's not the only one but it is one of the most common ones and so I wanted to talk about some of the the pros and cons of this thing so why would people do it and why should you be careful about doing it so pros and cons of this rapid test and the pro the first Pro is actually kind of in the name rapid so it's actually a really really quick test with a fast turnaround time so I can actually get the results usually within 15 to 30 minutes so the first advantage is that it's rapid and I'll say actually you can do the test itself in about less than 15 minutes usually so that's a huge advantage people have to wait around forever to find out if they have the flu now the the results is actually another advantage it tells you whether they had flu A or B so usually tells you flew a and or B and I say end or because a lot of them can actually detect both a and B but a few of them only do flu a or flu B in which case you would need to do a couple of tests to get the full results now a couple of disadvantages to using these rapid tests is that they don't tell you the precise H or n protein that is on that virus remember this is relevant for the type A viruses we said but these rapid tests they don't actually tell you which H and n virus you picked up so you wouldn't actually know which one you got and you also wouldn't know whether or not it was in the vaccine whether it was a vaccine strain that actually made you sick a lot of people like to know that because they think well would I have gotten sick if I had gotten the vaccine and unfortunately most of these rapid tests don't tell you that now finally and this is probably the most relevant one is that these tests are not perfect you know we like to think that you know if it's a flu test it'll tell you with absolute certainty whether or not you have the flu but actually they are not perfect and they they sometimes make some mistakes and I'm going to kind of talk through two of the mistakes that they sometimes make the first one I'm going to write them down here is let's put down here the flu test results so under flu test I'll tell you what the result was for my rapid test let's say it was positive so you're thinking as you walk out of the doctor's office if your flu test was positive that you have the flu but let's say in reality in a reality you actually don't maybe you have something else you have some other virus from some other illness that's causing your symptoms so that's a mistake obviously right the flu test obviously made a mistake there so we would call that false and this is kind of alluding to the fact that it's a mistake a false positive and the positive is because that was the result that it gave you so if you have a false positive then this is your situation it's telling you the flu test is telling you that you're positive but in reality you actually have a negative so that's the first type of mistake the second type of mistake is actually kind of the opposite it's called a false negative and you can kind of guess what that might mean right so a false negative again it's a mistake so that's what the false alludes to that's what the false part means that it's a mistake and if it's negative that means that over here the flu test is telling you that you don't have the flu but in reality you do so these flu tests are very good they're very helpful they're very fast they tell you if you have flu A and/or B but you gotta remember that they're not perfect and every once in a while they do make mistakes so just be aware of that fact