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Streptococcus pneumoniae and flu vaccines

Why do we need a new flu vaccine every year? Learn about the pneumonia and flu vaccines and how they help your body fight off infection. Created by Jannah George.

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  • hopper happy style avatar for user Maddie Bliss
    if we got a flu shot last year, wouldn't the same one protect us against it this year too?
    (9 votes)
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  • leafers seed style avatar for user Cleo  Man
    What does pneumococcal do to the body?
    (5 votes)
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    • aqualine seedling style avatar for user SpinosaurusRex
      Pneumococcal disease is an infection caused by Streptococcus pneumoniae bacteria (“pneumococcus”). These bacteria can cause many types of illnesses, including: pneumonia (infection of the lungs), ear infections, sinus infections, meningitis (infection of the covering around the brain and spinal cord), and bacteremia (blood stream infection). Pneumococcus bacteria are spread through coughing, sneezing, and close contact with an infected person.

      Symptoms of pneumococcal disease depend on the part of the body that is infected. They can include fever, cough, shortness of breath, chest pain, stiff neck, confusion and disorientation, sensitivity to light, joint pain, chills, ear pain, sleeplessness, and irritability. In severe cases, pneumococcal disease can cause hearing loss, brain damage, and death.
      http://wwwnc.cdc.gov/travel/diseases/pneumococcal-disease-streptococcus-pneumoniae
      (10 votes)
  • duskpin tree style avatar for user Bourgeois,Ryan
    Why was there a needle on this video?
    (1 vote)
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  • orange juice squid orange style avatar for user Zander
    Around , she talks about how each year the flu virus changes. Why exactly does the virus change? I mean, I know the basics, I know that it mutates slightly from what it was before, and that is what contributes to the fact that doctors recommend that we should get a flu shot every year, but what causes the virus to mutate?
    (4 votes)
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    • starky sapling style avatar for user Hannah Chavla
      According to the National Library of Medicine, in the following article, the fourth paragraph under the Introduction:
      "Viral mutation rates are not merely caused by polymerase errors, but also by the ability of a virus to correct DNA mismatches by proofreading and/or post-replicative repair. Furthermore, other sources of mutation include host enzymes, spontaneous nucleic acid damage, and even special genetic elements located within some viral genomes whose specific function is to produce new mutations (Fig. 1b). Mutation rates are modulated by additional factors, including proteins involved in replication other than the polymerase, the mode of replication, and the template sequence and structure. "
      Site: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5075021/
      Influenza viruses in particular tend to mutate quickly as they are RNA viruses, and characteristic of most RNA viruses, have a rapid mutation rate and large genetic assortment. Also, these viruses undergo frequent minor/major changes throughout each year through the processes of antigenic drift and antigenic shift.
      Another link: http://www.who.int/biologicals/vaccines/influenza/en/
      (4 votes)
  • marcimus pink style avatar for user songbird1999
    Why do people get the flu shot if they injecting them with it
    (1 vote)
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    • leaf green style avatar for user Joanne
      At in the video, she explains the micro organism, m.o., has been inactivated or killed prior to being injected into the patient. The 'shell' or inactivated m.o. still causes our white blood cells to attack it, and when they attack it, they do two things. 1. The active white blood cells form antibodies and destroy the inactivated m.o. (which could not cause disease anyway) and 2. They multiply and store 'memory' cells that will recognize this m.o. in the future if it comes into the body. She says they 'keep a picture' of them for future reference,she is trying to use that as an analogy for the memory cells.
      The purpose of a vaccine is to give the body exposure to a inactive or killed m.o. so the body has time to form a defense that is strong before the real m.o. enters the body. Something important to understand is how our immune system responds to disease. The first time we are exposed to a cold virus, within a few days, we have the cold. We have a runny nose and are sneezing for five days or so and then we get better. Why? The virus did not automatically quit, no that is not what happened. What happened is that our white blood cells got active and destroyed that cold virus! It is thanks to the white blood cells we got better! And when someone sneezes on you again a couple of weeks later and you inhale that live virus into your nose, you don't even sneeze or get a runny nose because your activated white blood cells are ready and they destroy it again. So the second time, you don't get sick or even know that you had the cold virus in your body. That is what a vaccine is doing, it is giving the patient that first exposure to a shell or dummy m.o. so the body can build an active group of white blood cells making antibodies and also have memory white blood cells waiting in the body for the 'second' time when the real or dangerous m.o. enters the body. From the body's point of view this is the second time it has seen this m.o. so it already knows how to destroy this dangerous m.o. Therefore, the patient will not get sick or show any signs, thanks to being vaccinated.
      (5 votes)
  • marcimus purple style avatar for user 163858
    Sometimes the flu shot does not work why do we need it?
    (1 vote)
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    • leaf green style avatar for user Joanne
      Vaccinations, especially when considering the influenza virus which mutates every year, are not perfect. However, even a vaccine that is 30% effective is better than being wide open , or having 0 chance of avoiding an infection when vulnerable for pneumonia and death. Some people can not get a vaccine and they rely on the rest of us to get vaccinated to reduce the potential of their disease. All health care workers should be vaccinated as well as anyone with vulnerable family members, young, old, on chemotherapy, immune compromise d etc.. Vaccines allow the many vaccinated people to protect the few vulnerable people. It is a low cost, effective way to protect the lives of many people with few risks. Check out this video.
      https://www.khanacademy.org/science/health-and-medicine/infectious-diseases/influenza/v/making-flu-vaccine-each-year
      (5 votes)
  • starky ultimate style avatar for user Ramon Xie
    I feel like I'm not understanding something correctly. If "coccal" refers to the sphere-shaped bacteria, why would we need a vaccine for it if it isn't a virus?
    (2 votes)
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    • leaf blue style avatar for user dysmnemonic
      Vaccinations are useful for some bacteria, too. They train the immune system so that it can react with adaptive immunity immediately if there's ever an infection. This is very useful for Streptococcus pneumoniae because it's an encapsulated organism, which protects it from innate immunity. By vaccinating with capsule proteins, the immune system can recognise and respond to S. pneumoniae, protecting against infection.
      (3 votes)
  • piceratops sapling style avatar for user Marinette Dupain Cheng
    Is there another way to administer vaccines?
    (1 vote)
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  • marcimus purple style avatar for user 163858
    We get a flu shot ever year we should not need to get it every year.
    (0 votes)
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  • starky tree style avatar for user SHAIKH MANZER ALAM
    How can flu virus change their shape? []
    (1 vote)
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Video transcript

Voiceover: So how many of us remember the first time we were shot? I don't mean by a gun, I mean by that. Our first shot, right, our very first vaccine, and I remember being at the doctor's office as a child, and going in and being vaccinated, just thinking it was the worst thing in the world ever cause it hurt so much! And then, I learned what vaccines are, and it was really helpful for me. So let's talk about that together. So I have two images here, let's get rid of that needle, it's pretty scary. So I have one of the influenza vaccine, labeled Flu, and one of the pneumococcal vaccine, labeled Pneumo. Now, if we're talking about the flu vaccine, we know that the flu vaccine is gonna protect us against the influenza virus. And we know that getting the flu is a pretty crummy thing. Now, we know that the flu vaccine can protect us against three or four different serotypes. So what does that mean? So the flu vaccine comes in a trivalent or a quadrivalent. And, what does that mean? So if you had a trivalent vaccine, it's gonna protect you against three different serotypes of the flu. And serotypes really means strains, right? So different types, whereas the quadrivalent can protect you against four different strains, or serotypes, of the flu. And that's really important with this type of vaccine and this type of virus, because we know that the flu vaccine changes on a yearly basis. And it's important that we're able to keep up with it and protect an individual against the most appropriate strain. And so how does that work? When I say the influenza virus changes, it really does. So let's say that one year, and we'll say this is 2012, that the flu vaccine, excuse me, that the flu virus looked like this. And then let's say that the next year, the flu virus looked like this. And then let's say that in another year it looked like this. So you see that it changes a little bit every single year. And that's why it's important that research and data are able to look at all these changes, and to figure out what the most likely virus is gonna be this year, to protect us against it. Now just like we have a flu vaccine that protects us against three serotypes or four, our pneumococcal vaccine's pretty similar in that we have vaccines that can protect us from anywhere from seven to 23 different strains, and that's pretty important too. Now if you notice in the name, the pneumococcals looks like pneumonia, and it should because pneumococcal diseases actually cause things like pneumonia, and ear infections, and meningitis, all the things that we don't want to get. It protects us against the pneumococci bacteria. So I'm going to go ahead and write pneumococcal, so we know what we're dealing with. Now, what do we have to know about these vaccines? These are inactivated vaccines, so what that means is that it's essentially the killed virus. So if we come over here, I'm gonna draw a picture, and let's say that this is the influenza virus. So, I'm gonna just make it round like this, and then I'm gonna put some green squiggly shell on the outside. Now I want to draw it like this so you can see something. So, if I said that this flu vaccine is inactivated, that means that it's killed. So what we do is we actually destroy the virus, so destroy the pathogen, destroying what causes the infection, what causes all the bad symptoms, but I'm gonna leave that protein shell intact. And I'm gonna leave it intact in the vaccine for a reason. I want the body to recognize this as a foreign invader and build up a defense to it. So how does that work? Let's scroll down here. Now I'm just gonna draw a blood vessel. Now remember that syringe that we saw earlier? That scary syringe? Let's say that that scary syringe has this flu vaccine in it, so it's gonna have this protein shell. So I'm going to draw this protein shell here in the body. Now what's gonna happen? It's been introduced into me through that scary needle, now my white blood cells are gonna show up to the scene. And we know my white blood cells, these are my security guards, right? This is my defense system, they're gonna protect me against anything that's coming to hurt me. In this case, my white blood cells recognize that this guy right here doesn't belong. And so what are they going to do? They're going to attack. So my white blood cells are gonna reach out and they're gonna beat up, or they're gonna attack this foreign invader. Now because this is an inactivated vaccine, that it's not really the flu virus, it's just the protein shell, it's not enough to make me sick. It is enough that my body recognizes it shouldn't be there, and it's going to beat it up, like we said, it's gonna attack it, going to destroy it, and it's gonna remember and put in it's imaginary pocket, it's gonna put in a picture of this flu, this flu virus. That way it's going to remember if this virus ever shows up again, I know how to beat you. Now, because it's still part of the virus, because it still has a protein shell, there's a small chance that it could manifest in us some very, very mild symptoms of the illness. But it's not enough to make us sick. Now who benefits from vaccines? Really anybody! But especially individuals that have lung disease, so let's just draw our lungs here. So, especially someone that has got chronic lung disease, like chronic obstructive pulmonary disease. Somebody that has emphysema. And the reason why they benefit from these vaccines is because they're more likely to get the disease, and they're less likely to be able to fight it off on their own. And then finally I'll end with this last thing. We have something called a vaccine information statement, and sometimes you might see it's called VIS, so Vaccine Information Statement, and this is really a piece of paper that we give to our patients, and you see that I just am writing Flu and Pneumo One here, and what it is, it's a sheet that has information about the vaccine so that the patients are aware of everything about it: what's in it, how it's made, what it's used for, and that way they're clear on the vaccine that they're receiving.