Articles, Blog

Do Surgical Masks Really Protect You from the Flu?

October 24, 2019

[ ♪ Intro ] Good news: It looks like we’ve finally made
it through this nasty flu season. Hopefully, thanks to a flu shot and lots of
hand-washing, you managed to avoid getting sick. Maybe you even went the extra mile this year
and put on a surgical mask to ward off germs in crowded, public places. After all, according to public wisdom, that
totally works, right? Well, it’s not that simple. That fetching paper mask might not have actually
prevented you from catching the flu — but if nothing else, if you were sick, it probably
stopped you from infecting everyone else. At first glance, those masks might seem really
effective — even according to some research. In one 2009 study, almost 450 nurses in Ontario,
Canada, were assigned to wear either a simple surgical mask or an N95 respirator. These are specially designed masks that mold
closely to the face and block at least 95% of tiny particles. That study, published in JAMA, found that
about 23% of nurses ended up catching the flu regardless of the form of protection they
used. So case closed, right? Masks must work at least as well as those
fancy respirators at keeping people flu-free. Except… that’s probably not the case. See, there’s a difference between getting
sick and being exposed to flu virus. And other studies have shown that surgical
masks are definitely worse at keeping out viruses. One of those studies, published in American
Journal of Infection Control in 2006, used samples of a harmless virus to test how good
respirators and surgical masks are at protecting their wearers from airborne pathogens. They found that 20 to 85% of the simulated
pathogens penetrated the surgical masks, compared to only around 5% for the respirators. Which is quite the difference. So even if both groups of nurses in that first
study got sick just as often, the ones wearing surgical masks were probably exposed to a
lot more particles. If you think about it, though, that really
isn’t that surprising. Because here’s the thing: Surgical masks
aren’t actually designed to protect you from dangerous particles in the environment. Only respirators are. Instead, the masks intended for the opposite
job — protecting other people from your germs. See, while respirators fit tightly to your
face, surgical masks often have gaps on the sides. They still do a good job covering your mouth
and nose, but outside particles can probably sneak in around the mask. So even if they do happen to keep you healthy,
that’s not their main purpose. Still, when it comes to containing your germs,
they’re definitely effective. For a 2013 study published in the journal
PLOS Pathogens, scientists collected examples of exhaled particles from about 40 flu patients
with and without surgical masks. They found that the masks significantly reduced
the amount of aerosolized virus that their subjects put into the air. And a 2009 study from the journal Clinical
Infectious Diseases found that surgical masks were just as effective as fancy respirators
at keeping the illness from spreading. This is why doctor’s offices will ask patients
who are coughing or sneezing to put on a mask while they’re in the waiting room — to
protect everyone else. According to a Mayo Clinic expert, if you’re
not sick yourself, just worried about catching the flu, wearing a paper mask might help,
and it certainly won’t hurt. But your best bet is still to suck it up and
go get that flu shot. Thanks for watching this episode of SciShow! And special thanks to Lorraine on Patreon
for asking, and to all our patrons who voted to have this question answered! If you’d like to submit a question or vote
on the next ones we answer, you can go to [ ♪ Outro ]


  • Reply Lutfa Lasker April 29, 2018 at 5:06 pm

    Random comment read by a Random viewer while watching this video

  • Reply Jamie Hinton April 29, 2018 at 5:09 pm

    Unless a medical professional tells you not to, just get a damn flu shot ?

  • Reply WarmWeatherGuy April 29, 2018 at 5:10 pm

    Getting your vitamin D level up is better than the flu shot. Google it.

  • Reply Rage Quit87 April 29, 2018 at 5:24 pm

    in Japan everyone who is sick wears a masks to stop other getting their germs. wish everyone did the same! I can stand when someone who’s coughing doesn’t cover their mouth!

  • Reply CrankyPants April 29, 2018 at 5:31 pm

    Nice job, as always, Olivia.

  • Reply Genisay April 29, 2018 at 5:32 pm

    I thought the point of the mask was to help stop from spreading germs when you are sick, not to help prevent you from getting sick.

  • Reply philosophy for a better life April 29, 2018 at 5:34 pm

    I got the flu in November, and by golly was it nasty, sick for a week and weeks recovering. Pains everywhere, I could barely get out of bed

  • Reply CrazyBeef April 29, 2018 at 5:42 pm

    well i didnt get sick and didnt have any symptoms, didnt have any form of special treatment against the flu for years, like 4 years. hurray for a healthy imunesystem (i am 17 years old)

  • Reply BuddyL April 29, 2018 at 6:44 pm

    2:00: [Surgical masks] protect OTHERS from YOUR germs."

    Plot twist!!!?

  • Reply Watermelonmaleesha April 29, 2018 at 7:01 pm

    no i just dont leave me room

  • Reply Equine Expert April 29, 2018 at 7:04 pm

    Olivia does a better job of presenting with every episode! Keep it up!

  • Reply Nerd In A Dress April 29, 2018 at 7:05 pm

    So why do doctors wear them then?

  • Reply Cloud Twirl April 29, 2018 at 7:46 pm

    And here i thought all of this was common sense…

  • Reply Olivia Anderson April 29, 2018 at 8:22 pm

    I hate masks because they fog my glasses when I breathe lol

  • Reply Harry 8642 April 29, 2018 at 8:50 pm

    Didn't have a shot, went mountain biking in -5°c and I haven't been I'll in 3 years (not even a cold) roll on natural selection!

  • Reply Lama April 29, 2018 at 8:55 pm


  • Reply Christian O. Holz April 29, 2018 at 8:57 pm

    Flu shots are overrated esp. for healthy people. The best way to protect yourself against illness is to live healthy and thereby maintain a strong immune system. It doesn't mean you'll never get sick, but it can greatly reduce the length and severity of a common illness like the flu. Viruses change and adapt all the time so getting a flu shot really only makes sense for those with compromised immune systems like the elderly or those with chronic illnesses that affect their immune systems

  • Reply _ISO_ April 29, 2018 at 9:22 pm

    Obviously no

  • Reply Sonja Morrison April 29, 2018 at 9:33 pm

    Interesting. Informative. Cool!

  • Reply JoeyPsych April 29, 2018 at 9:54 pm

    Why do people in the US get flushots? Is the flu so much more potent and dangerous overseas? In the Netherlands we only have flushots for elderly and physically weak (or ill) people, everybody else just deals with it. So either you be sick for a week, or you have a slight headache/nausea for two days, but in both cases you'll be fine after. Hearing about these flushots in the states almost makes it seem like a pandamic or something, as if it is a really deadly disease.

  • Reply John Matthias April 29, 2018 at 10:16 pm

    If I had to work in a hospital, I would want a Darth Vader level of isolation.

  • Reply rubymimosa April 29, 2018 at 10:27 pm

    I have lupus and get sick easily. If I think I’m getting sick, have been near someone sick or am visiting a newborn or the elderly I wear a paper mask to protect them from anything I may be incubating. Because I also have a lot of allergies (which I can’t be sure aren’t an incoming cold) I wear the mask a lot. I thought everyone commonly did this and I just wore one more often because I’m sick more often. Just common courtesy no?

  • Reply Gmodism Total Nerdery Channel April 29, 2018 at 10:55 pm

    Flu shot, how about eat decently and exercise from time to time, that keeps you better of

  • Reply Scerttle April 29, 2018 at 11:11 pm

    "We made it through this flu season" says the northerner.

  • Reply Darth Biomech April 29, 2018 at 11:30 pm

    Are people really that stupid to think that a piece of cloth is supposed to be a protection? Those things are supposed to be for the sick people! So they wouldn't spread germs around them in public places! Not reverse! The same reason why surgeons wear them – to not accidentally breathe on the patient's liver!

  • Reply GhengisJohn April 30, 2018 at 12:15 am

    The answer was exactly as I figured. Woot.

  • Reply sirBrouwer April 30, 2018 at 12:52 am

    The only thing that will keep out all airborne pathogens would be a independent respiratory system with sterilized Oxygen Supply.
    And to make it more secure were a new biohazard suit every time you leave the sterilized environment.

    The only food you can get are food products that have been freeze-dried and when you prepare the food always boil it for at least 20 minutes. Same with the water. Always boil it. Even water for the toilet and shower pre boil it always.

  • Reply 2010ngojo April 30, 2018 at 1:47 am

    Just wear both at the same time.

  • Reply Isaac Ezekiel The color blind guy April 30, 2018 at 5:31 am

    ? to be honest in Asian so I'm still gonna wear it (˶‾᷄ ⁻̫ ‾᷅˵)

  • Reply Stacy Stanton April 30, 2018 at 5:48 am

    Actually your best defense is to wash your hands often and thoroughly and to avoid touching your face. The flu shot helps, but it doesn't always keep you from getting sick.

  • Reply electronicsNmore April 30, 2018 at 6:18 am

    Never had a flu shot, and never had the flu……and I'm 45. Nano Mask works.

  • Reply Johnnie Walker April 30, 2018 at 7:06 am

    This is why ninjas never get sick.

  • Reply Lee Fisher April 30, 2018 at 8:56 am

    What’s a harmless virus ?

  • Reply ego bruiser April 30, 2018 at 12:02 pm

    you can keep the needle and the mask, my body works just fine without it all.

  • Reply Jason Melton April 30, 2018 at 12:13 pm

    Japan wears them to avoid getting other people sick

  • Reply MiguelPpM April 30, 2018 at 1:12 pm

    Idk with you… flu shots worked for me, never had it, also, being some poor ntion in asia, rarely anyone aside from prefession would wear masks, also I have weak imune system.

  • Reply Justin Ruiz April 30, 2018 at 2:52 pm

    3:10 Anti-vaccinators just makes no sense. Period.

  • Reply shadowthetwisted April 30, 2018 at 3:04 pm

    You can't catch the flu, if you are never around people.

  • Reply ThisIsNotPictureTube April 30, 2018 at 3:04 pm

    How to stop the flu: cough properly, morons.

  • Reply Daniel Dulu April 30, 2018 at 3:05 pm

    I just retired from the second worse job for germs that there is. Custodian in a school. The worst job is working in a hospital as anything. The last eiht years one of my jobs was disinfecting water fountains. Cannot remember the last time I had the flu and I would get two or three colds a year. Never took the flu shot, not because I am one of those against immunization freaks but because it seems they miss the mark every year as to the type.

  • Reply ocap68 April 30, 2018 at 3:23 pm

    Thank you for so much for this! I was recently diagnosed with Lupus and began the immunosuppressant treatment, so I have been wearing the paper masks every time I go out in public and crowded places. Now I will buy a proper respirator! Thanks again! 🙂

  • Reply IssieWeimo April 30, 2018 at 4:28 pm

    i wish there was a control which showed if the surgical masks were more effective than wearing nothing.. they got sick 23% wearing both but what about wearing nothing

  • Reply Sourcedrop April 30, 2018 at 4:32 pm

    I've never had a flu shot in my life. They're worthless.

  • Reply Gillian Fisher April 30, 2018 at 5:37 pm

    THANK YOU. I wish I could rewind time and show this to the 150+ people in my calculus III course! Like I get life doesn't stop when you're sick, but you can at least try and prevent the spread of your illness. Trying to concentrate when almost half of them were coughing up a storm was MADDENING.

  • Reply The Drowned Earth April 30, 2018 at 6:50 pm

    I thought it was common knowledge that masks don't stop you getting ill, but prevent you from infecting others.

  • Reply coffeeiv April 30, 2018 at 8:13 pm

    OMG I LOOOOVE your sweater!!! I want to knit it!!!

  • Reply ĐȺɍꝁnɇss April 30, 2018 at 8:30 pm

    Is it possible the masks could work as a placebo making people think they wont get or aren't ill

  • Reply xSPYDRx April 30, 2018 at 8:48 pm

    i barely wash my hands, i don't get flu shots, and i don't get the flu. i try and let my body be exposed to most of what nature has to throw at me, to keep it ready for the outside world.

  • Reply ompenarnie May 1, 2018 at 12:15 am

    This video begins with a false presumption then debunks it. The people who wear masks in public aren't trying to prevent themselves from getting ill, they're trying to prevent spreading their illnesses (which they present as their correct conclusion, then they recommend the highly ineffective flu shot). This channel has gotten extremely lazy. How disappointing.

  • Reply Dantick09 May 1, 2018 at 12:33 am

    No, your best bet is to buy air cilinders and a respirator

  • Reply Kaela Olsen May 1, 2018 at 2:17 am


  • Reply Quimper111 May 1, 2018 at 2:45 am

    What's with the camera zoom jumping back and forth like some complete moron edited this? Downvoted and aborted.

  • Reply Ali H May 1, 2018 at 3:21 am

    I’m so confused

  • Reply Angry Kittens May 1, 2018 at 5:42 am

    I always have this sneaking suspicion that most people wear those masks to feel like ninjas.

  • Reply Jack Thompson May 1, 2018 at 7:21 am

    Do you guys sell flu shots on the scishow store ?

  • Reply Dylan Mckerley May 1, 2018 at 10:12 am

    The flu shot did literally nothing this year so what's the point of getting one if I'm just going to get sick anyway

  • Reply dork yface May 1, 2018 at 6:36 pm

    Surely it's people sneezing into their hands or else spreading the disease via touching things that's a larger concern?

  • Reply Zuhair S May 1, 2018 at 9:07 pm

    Sadly I got some sort of bronchitis virus at the very end of winter. Took 3 weeks to heal and still have some vocal cord discomfort. FML

  • Reply Kikyo4815 May 2, 2018 at 8:24 am

    I thought people knew this.
    I thought people I saw wearing masks were sick, not trying to prevent getting sick.
    Good grief, I give strangers too much credit sometimes.

  • Reply bossmarion May 2, 2018 at 2:44 pm

    This girl looks like she has been sick most of her life.

  • Reply Cristhian Perez May 2, 2018 at 3:57 pm

    I would wear a mask when I'm sick, but I'm afraid others will judge me.

  • Reply Amelia Nannette May 2, 2018 at 5:20 pm

    This is the first video of Olivia I've seen that doesn't have a comment section full of people being nitpicky about her because they've decided they dislike her. I love Olivia as a host, so I'm glad to see people have (mostly) relented on all the vitriol towards her.

  • Reply Draegon May 2, 2018 at 6:25 pm

    You just need a good immune system.

  • Reply Sammie Tyler May 3, 2018 at 12:06 am

    Watching this while ill… that "well done, you've made it through flu season" at the start was really a stab in the heart haha

  • Reply sugarplumfairy May 3, 2018 at 7:39 am

    The nurses that got sick probably didn't wash their hands then touched their face after removing the mask ?

  • Reply Thesis Statement May 3, 2018 at 11:25 am

    20% to 85% is quite a large margin

  • Reply Alexis Rivera May 3, 2018 at 5:00 pm

    I'm guessing that since you are constantly breathing into the mask itself in these cases the warm air coming from your nose over time makes it an ideal breeding ground for germs and viruses. If that were the case switching masks more often might help a little bit too. (we would need studies about that too)

  • Reply thingfish May 3, 2018 at 9:22 pm

    Here's a thought: Men, wash your fuckin' hands after you use the bathroom. I'm a guy, and you'd be appalled at what I've seen.

  • Reply bob174d May 4, 2018 at 6:28 am

    Tfw you get the flu shot but still get the flu. 🙁

  • Reply White Hat May 4, 2018 at 11:36 pm

    Damn it, that SEPTUM piercing is back…. it's so DISTRACTING

  • Reply Mike Davey May 5, 2018 at 3:14 am

    Surgical masks may help prevent hand to mouth (and nose) contamination which is a big vector. Which is why hand washing is so important. On the other hand, if they are porous to the flu virus they might make it worse if the person is constantly re-arranging the mask. In other words, keep your fingers out of your nose.

  • Reply Kiz Torres May 5, 2018 at 3:12 pm

    In Japan (a densely populated country, specially in big cities) you are supposed to wear a mask as soon as you realise that you might have a cold/flu, so that you don't spread your germs onto everyone else.

  • Reply zenengineer May 6, 2018 at 2:37 am

    I designed these things back in the early 1970s when working on the East Coast. Fluted facial masks are paper-faced (typically nonwoven fibers, latex bonded) with a meltblown (usually PET) microfiber inner core. A few details….. Get them wet, replace them. Have a beard or mustache – worthless. Use more than a couple hours, replace them. Absolutely no barrier to "pure" virus, only aerosol forms and bacteria. Largest gaps are usually prevalent around the nose, if there is a flex metal nosebridge adjust as best as possible. Elastic ties much better than string ties. When in use, do as little talking as required. There are different grades of fluted masks – best ones are for OR use.

  • Reply Anonymous Anonymous May 6, 2018 at 3:31 pm

    They do. People with the flu thinks you are going to robb them and runs away.

  • Reply NaughtImp0rtant May 8, 2018 at 4:34 pm

    I wear them when I may be sick, to protect others, not to try to protect myself. So many lives could be saved if people swallowed their pride and made the minute effort to reduce spreading illness. Either stay home, or wear a mask, it isn't that hard.

  • Reply holymanlogin May 9, 2018 at 3:27 pm

    Does ring in your nouse give you some extra protection?

  • Reply Zev Taublieb May 10, 2018 at 8:08 pm

    Thank you so much for your videos! You guys do a fantastic job! I love it.

    I have some questions that I am having a difficult time finding the answer of.

    I live in a Sweden where in the summer will stay sunny except for two hours of the day. Do birds adjust when they sleep when it is sunny all day?

    We all love sleeping on beds. Did cavemen sleep on the ground? Did they make beds? I ask because maybe it is better for our back to sleep on the ground? But it is so uncomfortable!

    How do blind people go through a day? Do they need constant assistance or can they go to the grocery store, restaurant and find a lover?

    Would life be better blind or deaf?

  • Reply CaptainSugar May 10, 2018 at 10:28 pm

    Danggg itttt lol

  • Reply figweb May 11, 2018 at 4:28 pm

    Hello everyone over at the SciShow crew :)! I've a quick question for you: Is it possible to draw with your mind? I don't mean draw from memory, nor draw what you create in your mind, but rather by use of technology, and our imagination, draw, without ever touching a pen, a picture. I've always thought this question needed an answer, and hoped maybe you could had one! Thanks so much for your time: ~ Kyle

  • Reply Dollightful May 12, 2018 at 12:33 pm

    How are these masks with dealing with pollution? I live in Korea and wear one almost daily to protect myself from the crap blowing over from China. Is is all in vain?

  • Reply Johnny J May 14, 2018 at 12:59 am

    …except this year the flu shot was WAY off.

  • Reply Eric Rakes May 15, 2018 at 3:03 am

    I work in some microbiological messes – nursing homes and hospitals. Practical experience tells me that surgical masks primarily help to keep you from touching your face. Most viruses like the flu aren't so much aerosolized but the erm, residue? is just all over the place. So touching your face (especially nose / mouth) is a big way to get sick. If you ever wear one and go to scratch your nose, pull your lip, rub your chin, etc. then you'll see a practical reason to wear it. Also, yeah, get your flu shot annnnd wash your hands before and after you use the bathroom. Even just based on the bacterial culture results that I see and then looking at the door handles in some of these places… how quiet and unassuming but so surely contaminated… yeah I'll wash before handling any personal biz.

  • Reply Hoigwai May 15, 2018 at 10:01 pm

    I can say for me that I was always under the impression that the masks were to protect others from your infections, this is because the Japanese people that I follow always put a mask on when they were sick.

  • Reply Morgan Schodlatz May 17, 2018 at 4:57 am

    I can't breath through those masks. I can't stand stuffy air and so it boggles my mind how people can wear masks and sleep completely under the covers.

  • Reply Eric Coffman May 17, 2018 at 6:20 am

    Is it possible for a baby (fetus or smaller) to grow outside of the womb (such as artificial wombs)?

  • Reply MusiCanines - The Musical Dogs May 19, 2018 at 8:50 pm

    What if I wear underwear on my face?

  • Reply Vakus Drake May 26, 2018 at 11:14 pm

    Clearly the only reasonable decision is to wear a hazmat suit with an internal air supply.

  • Reply friggin149 July 19, 2018 at 11:51 am

    know how i prevent the flue? shake everyone's hands, eat with your fingers never wash them.
    then again… it might be the vaccines…

  • Reply kyou42 July 23, 2018 at 10:22 am

    Wasn't there a video about surgical masks not being effective unless they are replaced often enough? Did I imagine that?

  • Reply Ryan Johnston August 15, 2018 at 6:00 am

    Good video until you suggested the flu vaccine. Viruses are always changing, and they are different from place to place. Why would last year's vaccine created in Colorado work this year in Nebraska? Furthermore, vaccines are filled with nasty toxins: mercury, aluminum, formaldehyde, fetal tissue, and consequently are dangerous. They can cause mild reactions all the way up to brain damage and death. Furthermore, the build up of toxins help create cancer later in life. They are also known to stunt the development of subtle spiritual senses. Often times the only thing a flu vaccine will do is actually just give you the flu. I'm really tired of so called "scientists" pushing Big Pharma's for profit agenda.

  • Reply BruceGTheshark August 23, 2018 at 8:19 am

    Should think about the waste generated if they are barely effective for prevention. Wear when sick ?. Other reasons may be pregnant or something else very important in your life happening soon!

  • Reply Something Dreadful August 31, 2018 at 4:22 am

    I don't think I've ever had the flu.

  • Reply Tiger Lilly September 10, 2018 at 8:27 am

    thats what I thought. Im sick as a dog, and I have to go on an international 4 hour train journey tomo. hopefully i can find one of those surgicals so i dont give it to everyone else. in the swedish pharmcies it looks like they have everything but useful stuff like this. might go to a tatoo parlour and ask, tatooists frequently wear surgical masks.

  • Reply Princess YuBeace October 3, 2018 at 7:33 pm

    In me and my friend’s experiences, these mask do help reduce allergic reactions to stuff in the air.

  • Reply Asher da FLOOF October 10, 2018 at 12:11 am

    I wear a a dust mask because… 😀 i dont have to socialize and i look good in it!

  • Reply Dezak P October 17, 2018 at 11:19 pm

    i got my surgical masks for the flu season from amazon by a brand called Sky Hearts. super useful!

  • Reply super heros January 22, 2019 at 5:45 am

    I'm wear mask I don't want get sick protect myself chco hospital because

  • Reply eyeonus March 10, 2019 at 7:39 am

    Haven't watched, but I already know the answer. The masks are worn by the infected to help prevent them infecting others. It does nothing for the uninfected to wear them.

  • Reply Minute Riddles ! April 5, 2019 at 7:28 am

    The flu season in our country is January. I get a cold every January.

  • Reply alisoncircus September 11, 2019 at 3:53 pm

    In Japan, wearing masks IS done to keep from spreading disease. It catches the droplets from your breath. That's it. It doesn't protect the wearer, it protects the others around you. Exactly as described. It's a courtesy, like not going to work sick, or not using public transit when sick. It's for when you can't stay home, or when you're not sick enough to have to stay home. It's as ubiquitous as holding doors for the person behind you or taking your shoes off when you enter a home. Americans just sometimes have a tough time wrapping their heads around the idea of doing something for others' sake without benefit to themselves.

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