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Current time:0:00Total duration:13:49

Video transcript

I'm going to quickly sketch out a flu virus for you something like this and it has an envelope so this is our little envelope and on the inside of this envelope are eight chunks of RNA so let's draw out the RNA this is the genetic material and this genetic material among other things codes for proteins and so one of the proteins here is sitting on the outside I'm drawing it as if it looks like a little hand and the reason I do that is that because you know it reminds me that this H stands for hemagglutinin but it basically holds on to silac acid and that's how it gets inside of little cells and then there's another protein over here and I draw these as a pair of scissors just to kind of remind me that this one Nick's the silac acid this is called neuraminidase and a Nick's the salic acid and it helps it cut itself loose from the cell and so it can move on to other cells kind of helps with exiting and I haven't actually been drawing this other protein there's another one here and I'm going to draw it now this is called an m2 protein m2 but it's not actually found on all flu types it's actually found on flu a but actually not found on flu B so this is a really important difference between flu a and flu B and you'll see why because one of the medicines that we use now to treat flu and yes you heard me correctly that we do have antiviral medications you you probably heard from many people you know saying antibiotics only treat bacteria not viruses and that's true but we have a special word for these other drugs and actually do treat viruses and we call them antiviral drugs and there are a couple of them I'm actually going to write out some of the names so this is called amantadine or remand to Dean and it's kind of easy to remember that they are in the same class because they share a lot of the same letters and these two antiviral drugs they actually work on stopping or blocking the activity of this enzyme and I'm just kind of drawing it like a little negative sign that's just to remind you that it blocks the m2 so if you know that flu B doesn't have in - then you also know that these drugs then don't work against flu B these drugs don't even work that well against flu a because flu a has become quite resistant so remember resistance happens because there are little mutations and it turns out that flu a has kind of a mutated form of m2 so that it actually doesn't get blocked by amantadine and rimantadine quite so easily so unfortunately for us that's bad news and the CDC in 2012-2013 have recommended not using these drugs because there's so much flu a resistance so that's unfortunate but the good news is that we actually have a couple of other drugs so we have a drug called the oseltamivir and related to it you'll see with the spelling we have zan EMA vir and these of course share a lot of the same letters again and these two actually block the neuraminidase and this is actually in flew a and flew b so that's that's good news because it blocks both flu a and flu B and let me actually just write that down flu a and flu B that's important right so we have these two drugs and one of them is a pill this first one is a pill and the second one is kind of an inhaled powder so they're taken in different ways and another important difference between them this is something that we have to just kind of keep in mind is that there are age restrictions so you have to be a certain age to be able to take these medications and they differ between the two drugs and whether you're using it to treat or if you're using it to prevent getting sick from the flu there's a difference there - so there are age restrictions that we just have to keep in mind but overall you know I'm pretty happy at the fact that at least we have these options if we need to treat someone that's very sick from the flu so let's talk about that treatment then so what what if you have someone this happens to me all the time where someone comes in kind of frowny face because they're sick with the flu and you're thinking okay well this person obviously needs treatment so I'm going to write that at the top they need some sort of treatment and I guess the first question is why would I treat this person of course everyone's going to be frowny faced if they get the flu so why am i treating this person what makes them so special well one thing that could make them special is let's say that they're high-risk remember high-risk groups in our society in our community include real young kids so let's say under two years old or older folks let's say people over 65 years old it could be someone that's pregnant that's another high-risk group or it could be someone that has some sort of chronic disease and that can be like a lung disease like or asthma you know any sort of chronic disease that makes them ill maybe their immune system isn't working and that would be a group I would definitely consider treatment for now another group I'm going to put it just right below is let's say you have someone that's completely healthy you know young healthy person not pregnant they still might get treatment if you know there's you know maybe let's say a severe disease let's say they get really really sick you know they're just feeling awful and you know I'm worried about them and they might need to be hospitalized you know if they're very very sick or they get some sort of complication or they're going to get hospitalization anything like that then this is a person again I would be careful with and I would consider treatment let me bring up a little bit of space so this is the kind of group that I would definitely consider treatment in so what else should we think about or consider well the next question often that comes up is how soon do you need to start treatment you know when do you need to begin treatment or when do you start and of course the answer is going to be able as soon as possible but a bigger range on that would be within two days so really if they've started getting symptoms let's say a week ago I might still be inclined to treat them but I'd be more inclined if it had just started what other questions or consideration should we just kind of go through what about treatment so how long do you treat them for and generally speaking it's about five days so five days of either oseltamivir or zanamivir and sometimes it goes a little bit longer but usually it's just five days that's kind of a normal course so this is how I would manage someone that's being treated for flu but of course what if what if they're not being treated for it what if they come in and they're feeling fine let me ask you draw another face here this is a smiley face something like that I'm sure you're going to draw too so let's say there's two and we're going to deal with them separately so let me actually draw a line between them something like this so we've got two more cases both are feeling fine but they might need prevention another thing these drugs can do is prevent you from getting sick so prevention is important as well and let's say these folks are living in a home let me actually build a little nice house around my first smiley-faced person and I'll do the same around this second a smiley face person and let's say this first person this person gets a visit from someone who's feeling flu symptoms so this person comes to visit and our our friend our smiley friend is worried they think oh my gosh you know now I'm going to get sick so if they're high-risk and we went through some of the categories actually I should mention there are other categories not just these that I listed there are some others as well but if they're high-risk in some way then I would consider giving them you know a medication like you know assault time of year or as a nama vir to prevent them from getting sick now this whole bit about severe disease or hospitalization this doesn't really apply because they're not sick that obviously not going to have severe disease or hospitalization already what about this question of when would I start treatment well ideally again it's going to be within two days so within two days of their exposure we call the visit or whoever kind of made them worry that they might get the flu we call that the exposure and so really want to start treatment within two days and you also want to start prevention within two days so how long would you actually give them the medications for to prevent them from getting sick well it really depends is on whether or not they've had the vaccine so let's say they've had the vaccine the flu vaccine and they were high risk they got visited by someone or had an exposure for this person I'm thinking I want to treat them for two weeks or give them two weeks of medications and the logic is that if I give them two weeks then that basically covers them and then after that I would assume that the vaccine would kind of take hold because remember the vaccine takes two weeks to really take full effect so basically I give them a medication during that period of time when the vaccine isn't completely protecting them and then I expect their vaccine to kind of take over and for the rest of the flu season presumably they should have good protection so that would be my strategy now let's say that they cannot take the vaccine so no vaccine and maybe this person has you know a severe allergy or had a horrible reaction to the vaccine for whatever reason they cannot take the vaccine let's say well in this person if they can't take the vaccine or don't have the vaccine then for this person I would actually treat them for just one week one week after the exposure so if the exposure happened let's say you know today I'd basically and then let's assume it's not going to keep happening so one week after exposure would then make it next week is when I would stop the medication so in this scenario I'm protecting them with the medication against getting sick from this exposure but because they've had no vaccine if they have ongoing exposures let's say you know they get exposed again to flu let's say in three weeks then again they'd have to come back to me we'd have to do this all over again so it really is ideal to have that vaccine in your system to keep protecting you and preventing you from getting ill now in this second scenario let's say instead of having a visitor who sick let's say you've got people around you that are sick living in the same place as you now this person is you know obviously in a home with a group of folks so let's call that a group home and what we call this scenario is basically an outbreak so this person is living in an outbreak setting then many many people with flu are living together causing an outbreak to happen we really are worried about other healthy people like our smiley-faced friend from getting sick with the flu as well so in this setting who am I worried about who do I want to make sure it gets medications to prevent them from getting sick well we've got high risk people again living together so if people are living together and this could be you know senior citizens or could be you know chronic care facility or nursing home it really any kind of group setting where people are institutionalized and they're high-risk I'm going to be worried and I want to make sure that we consider prevention with one of these medications the oseltamivir or zanamivir and do I have to worry about severe disease or hospitalization well no again because here specifically I'm talking about the healthy person who happens to be in an outbreak so they're still healthy they're not hospitalized they don't have severe disease yet so the whole idea is to make sure they don't get those things right and when would I want to treat them well it's hard to really say within two days because that implies that something specific is happening when in fact during an outbreak you just have constant exposure right I mean everyone around you is sick you know let's say you go down to eat in the cafeteria everyone is sick so when you're having constant exposure we don't really think about you know within two days doesn't really make sense here so here I would just kind of be worried in general about this person and as far as treatment you really end up just treating everybody vaccine or no vaccine you treat everybody throughout the outbreak because the whole goal here is really to minimize the outbreak you don't want people to you know have all the horrible consequences of flu remember flu can kill people and can cause hospitalizations so to prevent all that because this is a high-risk group of people living together you really just treat throughout the outbreak and even one week after one week after the last case of flu is found after the last case so here unlike the scenario where you have just a single exposure because you have so many people in an outbreak that are sick and kind of exposing each other you basically just treat everybody with oseltamivir or zanamivir so now you see we have a couple of antiviral drugs and you see when we can use them to treat folks and also when we can use them to prevent folks from getting sick