Articles, Blog

Why do you need to get a flu shot every year? – Melvin Sanicas

October 20, 2019

All year long, researchers at hundreds
of hospitals around the world collect samples from flu patients and send them to top virology experts
with one goal: to design the vaccine
for the next flu season. But why do we need a new one every year? Vaccines for diseases like mumps
and rubella offer a lifetime of protection with two shots early in life. What’s so special about the flu? Two factors make the flu a tough target. First, there are more than 100 subtypes
of the influenza virus, and the ones in circulation
change from season to season. And second, the flu’s genetic code
allows it to mutate more quickly than many other viruses. The flu spreads by turning a host’s own
cells into viral production factories. When the virus is engulfed by a host cell,
it expels its genetic material, which makes its way to the nucleus. There, cellular machinery that normally
copies the host’s genes starts replicating viral genes instead, creating more and more copies
of the virus. New viruses are repackaged
and crammed into the cell until it bursts, sending freshly minted influenza viruses
out to infect additional cells. Most viruses follow this script. The trick with the flu is that its genetic
material isn’t DNA but a similar compound called RNA. And RNA viruses can mutate much faster. When cells synthesize DNA, a built-in proofreader recognizes
and corrects mistakes, but the RNA synthesis mechanism
doesn’t have this fail-safe. If errors creep in, they stick around
creating new variants of the virus. Why is this a problem? Because vaccines depend on recognition. The flu vaccine includes some of the same
substances, called antigens, found on the surface of the virus itself. The body identifies those fragments
as foreign and responds by producing compounds
called antibodies, tailor-made to match the antigens. When a vaccinated person
encounters the actual virus, the preprogrammed antibodies
help the immune system identify the threat and mobilize quickly
to prevent an infection. Those antigens are different
for every strain of influenza. If vaccination has prepared
the immune system for one strain, a different one may still
be able to sneak by. Even within the same strain of flu, those rapid genetic mutations
can change the surface compounds enough that the antibodies
may not recognize them. To make things even more complicated, sometimes two different strains combine
to create an entirely new hybrid virus. All of this makes vaccinating for the flu like trying to hit a moving
transforming target. That’s why scientists are constantly
collecting data about which strains are circulating and checking to see how much those
strains have mutated from previous years’ versions. Twice annually, the World
Health Organization pulls together experts to analyze all that data, holding one meeting for each hemisphere. The scientists determine which strains
to include in that season’s vaccine, picking four for the quadrivalent vaccine
in use today. In spite of the flu’s evasive maneuvers, in recent years, the group’s predictions
have been almost always correct. Even when flu strains mutate further,
the vaccine is often close enough that a vaccinated person who catches
the flu anyway will have a milder and shorter illness
than they would otherwise. Vaccination also helps protect
other people in the community who may not be medically eligible
for the shot by preventing those around them
from carrying the virus. This is called herd immunity. The flu shot can’t give you the flu. It contains an inactivated virus
that isn’t capable of making you sick. You might feel tired
and achy after getting it, but that’s not an infection. It’s your normal immune response
to the vaccine. Some parts of the world use,
instead of a shot, an inhaled vaccine that contains a weakened live virus. This is also safe for
the vast majority of people. Only those with impaired immune systems
would be at risk, but they’re typically
not given live vaccines. Meanwhile, scientists are working
to develop a universal flu vaccine that would protect against any strain,
even mutated ones. But until then, the hunt
for next year’s vaccine is on.


  • Reply Haha AHha December 12, 2018 at 12:07 am

    Every year? I don’t think I’ve received a shot for 3 years atleast

  • Reply Smol Nikanatsu December 14, 2018 at 1:24 am

    Would you recommend flu shots?

  • Reply Adria Orue December 14, 2018 at 11:39 pm

    How about the 5% of the population that can't get flu because of their allergic to it

  • Reply MysteryKitty 13 December 15, 2018 at 10:30 am

    I'm not gonna get sick
    (I'm going to probably get sick next week or new year)

  • Reply Holy Knight December 15, 2018 at 8:02 pm

    TED is smart people. Get a flu shot every week. The GOOD GOVERNMENT LEAGUE recommends you get vaccinated.

  • Reply Holy Knight December 15, 2018 at 8:04 pm

    Yes, these fake computer animations PROVE that you need a flu shot! Don't think for yourself, the smart people have already done that for you.

  • Reply lamp December 16, 2018 at 11:44 pm

    So basically it helps you.

  • Reply Ric Rovey December 20, 2018 at 7:43 pm

    Flu shots don't work and weaken the immune system

  • Reply Core Cubed2 December 22, 2018 at 5:20 pm

    If you visit senior loved ones, both you and they should consider getting a flu shot each year. I found this information helpful when determining which flu shot to get:

  • Reply a noobypro az December 24, 2018 at 5:55 am

    the problem is that, since there is only a very short period between each season, scientists can have no experiments about the flu shot's long-term effects
    what if it increases chances of other diseases after many years after the vaccination?

  • Reply Serving Him December 24, 2018 at 12:50 pm

    Flu shots are they way to kill you slowly

  • Reply Harrison Tan December 25, 2018 at 11:25 pm

    Um I’m in 2018

  • Reply Vanilla Gorilla December 27, 2018 at 6:30 pm

    I have the flu. I feel like I’m going to die. Harsh cough, coughing up phlegm, my sides, back, and back of neck hurt. I’m either too cold and shivering, or too hot, been more or less in bed for two days.

    I’m not going to forget my flu shot next year…

  • Reply Mike Holly December 28, 2018 at 5:11 am

    If you have a healthy immune system you don’t need the shot if you don’t have a healthy immune system the shot could do far more damage getting you sick

  • Reply ALEX L January 4, 2019 at 8:32 am

    never gotten a shot and dont see the point of getting one, flu is not a big deal

  • Reply A Random Person January 5, 2019 at 6:10 am

    what is the scariest part of getting a flu shot?

  • Reply Zhou Fu January 6, 2019 at 5:09 am

    and yet, there are anti-vaxxers

  • Reply picanteluke January 10, 2019 at 1:54 am

    I haven't gotten a flu shot since 2010 and I jabent gotten the flu since 2010, I'll pass on the shots thanks

  • Reply riha. January 11, 2019 at 9:31 am

    yikes i don’t do flu shots every year

  • Reply Truong Nhat Nam January 12, 2019 at 9:49 am

    so how about 2019?

  • Reply Shane the Colloidal Silver man January 13, 2019 at 3:28 am

    Vaccines are loaded with toxic poisons and aren't safety studied at all people that get them are the guinea pigs. I don't get shots there loaded with mercury and aluminum which so called creates antibody responses. But there's more to the immune system than just antibodies. I take colloidal silver which stops viral replication PERIOD. It's antiviral, antibacterial and antifungus. It's the most antimicrobial substance known to man. The best product to buy is sovereign silver because it is the smallest particle size, .8 nanometers and the purest silver 99.999 percent and pharmaceutical grade water when talking about purity here. This translates into no Argyria or blue skin in its 19 year history it's safe and very effective. Herd immunity doesn't exist and has never existed its false advertising. Other natural and very effective medicines are oil of oregano and olive leaf very efficient at flu viruses. Also increases the immune system something a flu shot can never do at all. Also consuming cleaner foods like organic and making sure your getting lots of vitamin D as well something that fights flus as well. It's about the law of the terrain not the germ theory PERIOD. If your eating junk food and taxing your liver and gi tract your more succeptible to getting sick you don't get sick from having a healthy diet I fact I barely ever get sick now. I've had people with snot and flus around me at work and it passes me by because if you eat clean you stay mean fighting machine inside your body. God bless hope this helps

  • Reply Bee Phenix January 18, 2019 at 4:24 am

    Long story short- the virus morphs and changes so you need a new shot every year

  • Reply Good Bye January 19, 2019 at 8:24 am

    Been years. Sick once. But I’ll update my system soon

  • Reply Sans15 January 20, 2019 at 1:21 am

    Wonder why I've never gotten the flu or a shot

  • Reply Jörgen January 21, 2019 at 11:22 pm

    I just found out I got it

  • Reply Guy Wensley January 22, 2019 at 11:31 pm

    Nobody needs these shots they are poison

  • Reply The On3_ January 24, 2019 at 5:44 am

    Subscribe to PEWDIEPIE!!!!!!!

  • Reply Kevin V January 25, 2019 at 10:14 am

    i think i got inhaled vaccines once…

  • Reply XamuraiS January 29, 2019 at 11:38 am

    I had flu many times, didn’t get flu shots

    But im alive

  • Reply graykitty 05 January 30, 2019 at 11:26 pm

    I find it funny how everyone is arguing about the shot, and I’m just here like, “Ha. I CANT get the flu shot.” XD

  • Reply poop February 1, 2019 at 3:50 pm

    it ain't hurt

  • Reply poop February 1, 2019 at 3:51 pm

    I got the flu twice

  • Reply ClassyShows February 3, 2019 at 5:23 pm

  • Reply Username Generic February 5, 2019 at 6:58 am

    Vaccines? Pffft I got essential oils that I rub on my kid and He looks gre- oh and he’s dead

  • Reply Dorien Foroutani February 7, 2019 at 3:24 pm

    I haven't had a flu shot for 5 years and I'm perfectly fine :/
    my immune system is just too strong for the virus I guess
    I haven't been seriously sick for 6 years straight so that might be why

  • Reply TrollFox February 7, 2019 at 6:53 pm

    What a great idea, Injecting mercury and aluminum into yourself wow.
    I have proof go to a flu shot manufacturer website and check the ingredients in flu shots.

    Edit: Yeah they are low doses of it, but constantly getting flu shots every 6-12 months will build up and can cause further problems. Oh plus even if it didn't harm you you're still injecting metals into yourself

  • Reply Angle Sparkle118095 February 8, 2019 at 10:27 am

    I got flu shot just now i cried it was soooo pain

  • Reply Gamer King Luke February 9, 2019 at 5:00 am

    i dont get the flu shot

  • Reply Carter Nelson February 9, 2019 at 3:53 pm

    2019? Anyone?

  • Reply Gacha Lizz February 9, 2019 at 10:20 pm

    You dont need them it's not "MANDATORY."

  • Reply Mr.McYeetus February 10, 2019 at 11:29 pm


  • Reply asuka February 11, 2019 at 3:13 am

    Anti-Vaxxer: HeY stOp VaCCinEs aRe baD thEy CAusE auTisM iN chiLdrEn

  • Reply Cassandra Compton February 11, 2019 at 3:48 am

    I missed my flu shot this year and I’m probably not getting the shot this year but I’m never sick so lucky me

  • Reply Cross Fire February 11, 2019 at 4:04 pm

    Lol I have my life! Apparently I got a strain last week not covered by this year's vaccine! And now I am DYINGGGGGGGG

  • Reply AnonymousHater February 11, 2019 at 4:14 pm

    Insert your average

    VaCcInEs KaUsE AuTiSm


  • Reply Aws February 13, 2019 at 3:01 pm

    People outside America learn this at age 5.

  • Reply Michael Alberto February 14, 2019 at 9:33 am

    I dont take flu shots every year and im still healthy af

  • Reply Binozia - Tech February 15, 2019 at 8:08 am

    I’ve never had the flu before but I’m very curious about it now

  • Reply wow February 16, 2019 at 4:18 am

    *anti-vaxxers have entered the chat*

  • Reply wow February 16, 2019 at 4:27 am

    Thank you for scaring me into getting annual flu shots.

    Last time I got one was Three years ago

  • Reply garlic69 February 16, 2019 at 5:02 am

    when will there be a vaccine for ligma

  • Reply DangoDroping February 16, 2019 at 6:46 am

    it is 2019 who watches in 2019?

  • Reply IsThisAThing Or Not? February 16, 2019 at 9:27 pm

    Now I have gotten the flu once…

    Let's just say.. it wasn't fun at all…

  • Reply Lucas Glenn February 17, 2019 at 11:46 pm

    I bet there will be at least 1 anti-cancer comment.

  • Reply Eesha Sharma February 18, 2019 at 3:58 am

    Antivaxxers: i dont think so

  • Reply LuaConstructor February 20, 2019 at 11:33 am


  • Reply Gian Vertu February 20, 2019 at 4:32 pm

    This comment section gave me the flu

  • Reply J H February 21, 2019 at 10:11 pm

    The flu vaccine is 10-30% effective and doctors and even doctors and scientists say this. The fact that research shows vitamin D is more effective at preventing the Flu than the actual flu vaccine is pathetic. Most people who have got the Flu vaccine received the flu right after.

    Also about vaccines like MMR. If they provided lifetime immunity then why did people vaccinated also get Measles in the Washington outbreak? Oh right, vaccines don’t provide immunity for everyone.

  • Reply Lost Wonderer February 27, 2019 at 11:22 am

    I hope we can create a vaccine that destroys all flu types

  • Reply IncoherentSasquatch March 5, 2019 at 2:57 am

    Anti-vaxers are a special breed of uneducated.

  • Reply Makayla Johnson March 13, 2019 at 11:42 am

    Me:I want a vaccination
    Mom: you can’t have a vaccination
    Me:I am going to die…

  • Reply Ghh:;:; : ;; : ; ; :77 Iwndj ;:!: ; ; April 3, 2019 at 5:24 am

    So you don’t get the flu. Obviously

  • Reply realm313 April 16, 2019 at 5:47 pm

    No mention that flu shots contain multiple toxins such as formaldehyde(cancer causing), mercury, & aluminum. And where's the video about why you should NOT get a flu shot every year?

  • Reply Silence DoGood April 17, 2019 at 11:17 am

    Not worth the risk half the time they do not work!

  • Reply Summer Starlight April 18, 2019 at 4:14 am

    I got my flu shot today and I didn’t even feel anything. Funny thing is, I was the most stressed about it.
    But now my arm aches and I feel sick for some reason ;-;
    Edit: and this is why you don’t comment before watching the full video.

  • Reply Thales pro999 May 4, 2019 at 6:08 pm

    60% – flu shots
    39% – vodka shots
    Me – bullet shots

  • Reply generic May 9, 2019 at 2:33 am

    the animation is amazing

  • Reply Rock C May 12, 2019 at 4:39 am

    Nah I pass

  • Reply Jaarie May 19, 2019 at 9:45 pm


  • Reply axiom May 26, 2019 at 11:23 pm

    People that rarely get ill dont push themselves. "I have a strong immune system"… no you're just lazy and barely get out. Go to the gym 6 days a week, push yourself. You'll get ill.

  • Reply Peter Burton May 27, 2019 at 3:57 pm

    I got mercury poisoning from vaccines. My daughter went mentally backwards a couple of years and my neice nearly died from a reaction to the vaccine.

    My daughter and I took gluten, diary and wheat out of our diets and detoxed the heavy metals from the vaccines from our bodies and now we're both great. My daughter went from bottom of her class to above average. I'm amazed how well she's doing! Her speech and writing were terrible. Now she's pronouncing words well and reading her own books. I am blown away.

    By all means be good little sheeps and get your vaccines. Enjoy the mercury, aluminium and round-up present in them.

    Research yourself via duckduckgo (which won't [email protected] truth). Agenda 21 the plan to cull the population

  • Reply Marie Apple May 28, 2019 at 11:20 pm

    Since I almost died from the swine flu shot and booster I can guarantee no way Jose!

  • Reply Rst Acr June 7, 2019 at 4:18 am

    So interesting

  • Reply Evan June 7, 2019 at 7:47 am

    Because the mind control drugs wear off?

  • Reply cing earth cingearth June 8, 2019 at 12:35 am

    getting the flue injection and your chances of caching the flue increase !

  • Reply Kitty Girl June 9, 2019 at 2:06 pm

    they want to give everyone flu shots because they get lots of $$ from it
    even though most places say the shots r free they get paid for every person they give the shots to

  • Reply Rebecca Brown June 15, 2019 at 5:50 am

    Is your vid for little kids? Not a fan of being talked down to. Plus, it's not at all scientific.

  • Reply Sound Offense June 25, 2019 at 10:14 pm

    i freakin hate the god damn flu lol

  • Reply Dorothy Isidro June 29, 2019 at 8:42 pm

    Anti vaxx pepole: TRIGGERED

  • Reply Dorothy Isidro June 29, 2019 at 8:43 pm

    This is a video game called
    "Attack of the Flu – Viral busters"

  • Reply Random channel that has content July 11, 2019 at 3:58 am

    no you don’t
    I am on what you can say
    I get them every 2-3 years
    But if you don’t get them in general you die instantly

  • Reply Lee Hong Hui July 13, 2019 at 11:18 pm

    4:26 If it is really successful, why not the vaccine come in a spray

  • Reply Dontae Mcnamee July 14, 2019 at 11:36 am

    My sister had one but she’s still Alive life

  • Reply Roy requires WiFi July 21, 2019 at 11:45 pm

    Diseases that are very diverse that isn’t one single disease or fast mutating are hard to curr

  • Reply Adrian? August 2, 2019 at 6:29 am

    children of anti vaxx parents cry in dead

  • Reply Lay Lobinson August 8, 2019 at 3:40 pm

    Havent gotten a shot in over 2 decades and im as healthy as can be.

    Let food be thy Medicin.

  • Reply Irene Phua August 9, 2019 at 2:17 am

    The real question is why is everything pixelated.

  • Reply Bryan Yong August 9, 2019 at 1:19 pm


    Vaev, used tissue

  • Reply Nekaga Kitty August 14, 2019 at 2:20 pm

    I didn’t know we were suppose to get flu shots every year. I don’t think I’ve had one, mommy doesn’t trust them. She’s fine with vaccines though

  • Reply BmnGameBoy August 14, 2019 at 3:46 pm

    Jokes on you, we don't have flu shots here

  • Reply Hugh Gasey August 15, 2019 at 12:26 am

    Doughnut maker: Why you need to eat my doughnuts every day

    Ice cream man: Why you need to eat my ice cream every day

    Hamburger Joint: Why you need to eat our hamburgers every day

  • Reply Marshmallow Kitty August 19, 2019 at 2:14 am

    Lol I'm not having them every year. But just thinking about it makes me scared

  • Reply Scarlet Parra August 23, 2019 at 3:05 am

    One time I was too scared to get a flu shot and I ended up getting the flu and I survive

  • Reply Sakineu Beng August 26, 2019 at 3:27 pm

    Flu shot? What is that? Idk and it's been more than a decade since i had vaccinated back then in primary school

  • Reply Fat Boi September 7, 2019 at 2:46 pm

    This is all fake it’s just a fake lie! Clearly vaccines cause autism the government only wants money!!

  • Reply nosuchthing8 September 7, 2019 at 2:55 pm


  • Reply Agshin Yusifzada September 13, 2019 at 9:50 pm

    Very common to hiv

  • Reply seahawkfan1995 September 19, 2019 at 3:32 pm

    I've been getting it for 5 years no problems

  • Reply Dorothy Isidro October 13, 2019 at 12:54 pm

    Viruses vs Vaccines
    The game

  • Reply Alucard Lord October 17, 2019 at 4:45 am

    If viruses are non living things, how do they make vaccines from dead or weakened virus if theyre not alive? Hmm

  • Leave a Reply